Keyword Index

Home › Keyword Index

Keyword Index

Every page in this wiki, A–Z. marks an tiko-lang addition.

A · B · C · D · E · F · G · H · I · J · K · L · M · N · O · P · Q · R · S · T · U · V · W · X · Y · Z · #

A

Name	What it does	Category
#assert	Preprocessor conditional directive.	Preprocessor
Abs	Returns the absolute value of a number.	Mathematical Functions
AbsChecked	Returns the absolute value as an Optional, empty for the most negative value.	Math Library
AbsolutePath	Returns the full form of a path against the current folder; the path need not exist.	Filesystem
AbsSaturating	Returns the absolute value; the most negative value becomes the maximum instead.	Math Library
Abstract	Declare abstract methods.	User Defined Types
Access	Limits a Binary or Random file in Open to reading, writing, or both.	File I/O Functions
Acos	Returns the angle in radians, from 0 to pi, whose cosine is the number.	Mathematical Functions
Acosh	Returns the inverse hyperbolic cosine of a number of 1 or more.	Math Library
Add	Adds source and destination colour values with Put, capped at 255.	2D Drawing Functions
Add	Adds a key and value if the key is new; an existing value is left alone.	Map
Add	Adds a value; returns false if it was already there.	Set
Add	Adds 1, or a given amount, to the work outstanding; call it before the spawn.	Goroutines and Channels
Add	Adds one value to a running count, mean, variance, minimum and maximum.	Math Library
AddCalendarDays	Adds calendar days, keeping the same clock time across a DST change.	Date and Time (Chrono)
AddCalendarMonths	Adds calendar months, then works out the UTC offset again for the new date.	Date and Time (Chrono)
AddChecked	Adds two integers, returning an empty Optional if the result would overflow.	Math Library
AddDays	Adds days of exactly 24 hours, so the clock time can shift across a DST change.	Date and Time (Chrono)
AddMonths	Adds calendar months and leaves the UTC offset untouched.	Date and Time (Chrono)
AddProduct	Adds an amount times a rate to a running total, rounding only once at the end.	Finance
AddSaturating	Adds two integers, clamping the result to the type's minimum or maximum.	Math Library
AddScaled	Adds an amount times a fraction, such as one third, to a running total exactly.	Finance
AddSink	Attaches a sink to the logger, which keeps a pointer to it and does not own it.	Logging
AddWrapping	Adds two integers and wraps around on overflow, on purpose.	Math Library
Alias (Modifier)	Modifies the data type name mangling (decoration) of a public symbol.	Standard Data Types
Alias (Name)	Clause of the Sub and Function statements that provides an alternate internal name.	Procedures
Allocate	Reserves a number of bytes and returns a pointer to them, or 0; the bytes are not cleared.	Memory Functions
Alpha	Blends pixels with Put by each pixel's alpha, or by one alpha value you give.	2D Drawing Functions
Alphabetical Keywords List	Alphabetical listing of keywords, macros and procedures.	Language Documentation
And (Graphics Put)	Combines source and destination pixels with a bitwise And, as a Put method.	2D Drawing Functions
Angle	Returns the angle between two vectors in radians, from 0 to pi.	Math Library
Any	The Any keyword is used as a placeholder for a type or value in various ways.	Procedures
Append	Opens a text file with Open to add to its end, creating the file if needed.	File I/O Functions
AppendAllText	Adds text to the end of a file, creating the file if it is not there.	Filesystem
Apportion	Splits a Currency total by weights into parts that add up to it exactly.	Finance
Arithmetic Operators	Operators that can be used in mathematical expressions.	Operators
Array	Holds a growable list of values in order, reached by position from 0.	Array
Array Container		Array
Array Functions	Statements and procedures for working with arrays.	Array Functions
Array Results		Array Results
ArrayIterator	Holds a position in an Array; steps with IsValid, Value and MoveNext.	Array
Arraylen	Returns the total number of elements in an array, counting every dimension.	Array Functions
Arraysize	Returns the total size of an array's elements in bytes.	Array Functions
As	Part of a declaration which specifies a data type, or part of the Open statement which specifies a file handle.	Miscellaneous Keywords
Asc	Returns the character code at a position in a string.	String Functions
Asin	Returns the angle in radians, from -pi/2 to pi/2, whose sine is the number.	Mathematical Functions
Asinh	Returns the inverse hyperbolic sine of a number.	Math Library
Asm	Code block that allows the use of architecture-specific instructions.	Programmer's Guide
Assert	Debugging macro that halts program execution if an expression is evaluated to 0 (false).	Miscellaneous Keywords
AssertWarn	Debugging macro that prints a warning if an expression evaluates to 0.	Miscellaneous Keywords
Assignment Operators	Operators that assign values to operands.	Operators
At	Returns a reference to the element at a position, like a[ i ].	Array
Atan2	Returns the angle in radians, from -pi to pi, of the point at x, y.	Mathematical Functions
Atanh	Returns the inverse hyperbolic tangent of a number between -1 and 1.	Math Library
Atn	Returns the angle in radians, from -pi/2 to pi/2, whose tangent is the number.	Mathematical Functions

B

Name	What it does	Category
Back	Returns a reference to the back value without removing it.	LinkedList
Base (Initializer)	Specifies an initializer for the base UDT in derived Udt constructors.	User Defined Types
Base (Member Access)	Provides explicit access to base type members in non-static methods of a Type.	User Defined Types
Beep	Produces a beep sound.	Miscellaneous Keywords
Between	Returns the text between two delimiters.	String Library
Bin	Returns a number as binary text.	String Functions
Binary	Opens a file with Open for reading and writing bytes at any position.	File I/O Functions
Bit	Returns -1 if the numbered bit of an integer is set, or 0 if it is clear.	Bit Manipulation
Bit Manipulation	Macros that work with the bits and bytes of numbers.	Bit Manipulation
BitReset	Returns a copy of an integer with the numbered bit cleared to 0.	Bit Manipulation
BitReverse	Reverses the order of all the bits in the value's type.	Math Library
BitSet	Returns a copy of an integer with the numbered bit set to 1.	Bit Manipulation
BitWidth	Returns how many bits the value needs, or 0 for zero.	Math Library
Bitwise Operators Truth Tables	Computed values for the bitwise logical operators.	Language Documentation
BLoad	Loads a BMP file or BSave data onto the screen or into memory.	2D Drawing Functions
Boolean	Standard data type.	Standard Data Types
BSave	Saves memory or the screen to a file, as a BMP image if the name ends in .bmp.	2D Drawing Functions
Byref (Function Results)	Specifies that a function result is returned by reference.	Procedures
Byref (Parameters)	Declaration specifier to explicitly pass a parameter by reference.	Procedures
Byref (Variables)	Declares a reference.	Variable Declarations
Byte	Standard data type: 8 bit signed.	Standard Data Types
ByteSwap	Reverses the order of the bytes, converting between big-endian and little-endian.	Math Library
ByVal	Declaration specifier to explicitly pass a parameter by value.	Procedures

C

Name	What it does	Category
CAbs	Returns the modulus, the distance from zero, without overflowing for large parts.	Math Library
CAcos	Returns the inverse cosine of a complex number, or of any real number.	Math Library
CAcosh	Returns the inverse hyperbolic cosine of a complex number, or of any real number.	Math Library
CAcot	Returns the inverse cotangent of a complex number; zero gives zero.	Math Library
CAcoth	Returns the inverse hyperbolic cotangent of a complex number.	Math Library
CAcsc	Returns the inverse cosecant of a complex number, or of any real number.	Math Library
CAcsch	Returns the inverse hyperbolic cosecant of a complex number.	Math Library
Call	Statement to invoke a subroutine.	Procedures
CAllocate	Reserves memory for a number of elements, set to zero, and returns a pointer or 0.	Memory Functions
Cancel	Cancels the context and every context made from it; a second call is harmless.	Goroutines and Channels
CanonicalPath	Returns the real path with links resolved; it must exist unless allowMissing is true.	Filesystem
Capacity	Returns how many elements fit before the array has to grow.	Array
Capacity	Returns the number of slots in the table, always a power of two.	Map
Capacity	Returns the number of slots in the table, always a power of two.	Set
CArg	Returns the phase angle of a complex number in radians, from -pi to pi.	Math Library
Case	Control flow statement.	Control Flow Statements
CAsec	Returns the inverse secant of a complex number, or of any real number.	Math Library
CAsech	Returns the inverse hyperbolic secant of a complex number.	Math Library
CAsin	Returns the inverse sine of a complex number, or of any real number.	Math Library
CAsinh	Returns the inverse hyperbolic sine of a complex number.	Math Library
Cast	Converts a value to any named type, such as Cast(Byte, flag).	Converting Data Types
CAtan	Returns the inverse tangent of a complex number.	Math Library
CAtanh	Returns the inverse hyperbolic tangent of a complex number, or of any real number.	Math Library
CBool	Converts a number, or the text "true" or "false", to a boolean; zero gives false.	Converting Data Types
Cbrt	Returns the cube root of a number, negative numbers included.	Math Library
CByte	Converts a number or string to a Byte, rounding to the nearest; no overflow check.	Converting Data Types
CConj	Returns the conjugate, the same number with its imaginary part negated.	Math Library
CCos	Returns the cosine of a complex number.	Math Library
CCosh	Returns the hyperbolic cosine of a complex number.	Math Library
CCot	Returns the cotangent of a complex number, one over the tangent.	Math Library
CCoth	Returns the hyperbolic cotangent of a complex number, one over its tanh.	Math Library
CCsc	Returns the cosecant of a complex number, one over the sine; zero gives zero.	Math Library
CCsch	Returns the hyperbolic cosecant of a complex number, one over its sinh; zero gives zero.	Math Library
CDbl	Converts a number or string to a Double.	Converting Data Types
cdecl	Specifies a cdecl-style calling convention in a procedure declaration.	Procedures
Ceil	Rounds up, towards positive infinity, so Ceil(-2.7) is -2.	Math Library
Ceiling	Returns the amount rounded up to a whole unit, towards positive infinity.	Finance
CExp	Returns e raised to a complex power.	Math Library
Chain	Runs a program without arguments, waits, and returns its exit code or -1.	Operating System Functions
Channel	Holds a typed queue between goroutines; copies share it, and a new one is nil.	Goroutines and Channels
Channel.Capacity	Returns the buffer size the channel was made with; 0 means each value is handed over.	Goroutines and Channels
Channel.ChannelIterator	Holds a for each loop's place while it receives from a channel.	Goroutines and Channels
Channel.Close	Marks that no more values will be sent; values already buffered are still delivered.	Goroutines and Channels
Channel.Count	Returns how many values are buffered right now, as a snapshot.	Goroutines and Channels
Channel.GetIterator	Returns the iterator a for each loop uses to receive until the channel is drained.	Goroutines and Channels
Channel.IsClosed	Returns true once the channel is closed, even while values are still buffered.	Goroutines and Channels
Channel.IsNil	Returns true for a default-constructed channel, which blocks forever if used.	Goroutines and Channels
Channel.Receive	Receives a value, waiting for one; returns false once closed and drained.	Goroutines and Channels
Channel.ReceiveFor	Receives a value, waiting at most ms milliseconds; false on a timeout or end of stream.	Goroutines and Channels
Channel.RecvChan	Holds a receive-only view of a channel, which cannot send to it or close it.	Goroutines and Channels
Channel.Send	Sends a value, waiting for room or a receiver; raises an error if the channel is closed.	Goroutines and Channels
Channel.SendChan	Holds a send-only view of a channel, for a procedure that only produces.	Goroutines and Channels
Channel.SendFor	Sends a value, waiting at most ms milliseconds; returns false on a timeout.	Goroutines and Channels
Channel.TryReceive	Receives a value only if one is ready; returns false if empty or closed.	Goroutines and Channels
Channel.TrySend	Sends a value only if it can go at once; returns false if it would have to wait.	Goroutines and Channels
ChDir	Changes the current folder; returns 0 on success or -1 on failure.	Operating System Functions
Choice	Returns one element of an array picked at random, by reference.	Math Library
Chr	Returns a string made from one or more character codes.	String Functions
Chrono Date and Time		Date and Time (Chrono)
CImag	Returns the imaginary part of a complex number, without the i.	Math Library
CImaginaryOne	Returns the imaginary unit i.	Math Library
CInfinity	Returns a complex number whose two parts are both positive infinity.	Math Library
CInt	Converts a number or string to an Integer, rounding to the nearest; no overflow check.	Converting Data Types
Circle	Draws a circle, ellipse or arc, optionally filled.	2D Drawing Functions
CIsFinite	Returns true if both parts of a complex number are finite.	Math Library
CIsInfinite	Returns true if either part of a complex number is infinite.	Math Library
CIsNaN	Returns true if a complex number is NaN; one infinite part makes it infinite instead.	Math Library
CIsReal	Returns true if the imaginary part of a complex number is zero.	Math Library
CIsZero	Returns true if both parts of a complex number are zero.	Math Library
Clamp	Limits a value to a range: below lo gives lo, above hi gives hi.	Math Library
Class	Declares a type that always extends object: it has a vtable, run-time type information, and may implement interfaces.	Interfaces
Classify	Returns whether a value is NaN, infinite, zero, subnormal or normal.	Math Library
Clear	Sets a number of bytes, starting at a variable, to zero or to a given value.	Memory Functions
Clear	Removes every element but keeps the allocated room.	Array
Clear	Removes every entry.	Map
Clear	Removes every value.	Set
Clear	Removes every value and frees its nodes.	LinkedList
Clear	Empties the Optional, releasing whatever its value held.	Optional
ClearFpException	Clears one floating-point exception flag and leaves the others alone.	Math Library
ClearFpExceptions	Clears every floating-point exception flag.	Math Library
ClearSinks	Detaches every sink, without destroying any of them.	Logging
ClipLeft	Removes a number of characters from the start.	String Library
ClipRight	Removes a number of characters from the end.	String Library
CLng	Converts a number or string to a 32-bit Long, rounding to the nearest; no overflow check.	Converting Data Types
CLngInt	Converts a number or string to a 64-bit LongInt, rounding to the nearest.	Converting Data Types
CLog	Returns the natural logarithm of a complex number, or its logarithm to a given base.	Math Library
CLog10	Returns the base-ten logarithm of a complex number.	Math Library
CLogAbs	Returns the logarithm of the modulus, without overflowing for large parts.	Math Library
Close	Closes one or more file numbers, or every open file when given none.	File I/O Functions
Cls	Clears the screen, or only the text or graphics viewport.	Console Functions
CNaN	Returns a complex number whose two parts are both NaN.	Math Library
CNegate	Returns a complex number with both parts negated.	Math Library
CNorm	Returns the modulus squared, the cheap way to compare sizes.	Math Library
CNthRoot	Returns any one of the n nth roots of a complex number.	Math Library
Color	Sets the colours for text printed from now on, and returns the previous ones.	Console Functions
Command	Returns command-line argument n, the program's name for 0, or all of them if omitted.	Operating System Functions
Common	Variable declaration and scope modifier.	Modularizing
Compiler Error Messages		Using the FreeBASIC compiler
Compiler Option: -a	Add an object file to the linker's list.	Using the FreeBASIC compiler
Compiler Option: -arch	Set target architecture for improved/restricted code generation or cross-compiling.	Using the FreeBASIC compiler
Compiler Option: -asm	Set assembler format for inline assembly under -gen gcc.	Using the FreeBASIC compiler
Compiler Option: -b	Add a source file to compilation.	Using the FreeBASIC compiler
Compiler Option: -buildprefix	Set the internal buildprefix option.	Using the FreeBASIC compiler
Compiler Option: -C	Do not delete the object file(s)	Using the FreeBASIC compiler
Compiler Option: -c	Compile and assemble source file only, do not link.	Using the FreeBASIC compiler
Compiler Option: -d	Add a preprocessor definition.	Using the FreeBASIC compiler
Compiler Option: -dll	Create a DLL and import library.	Using the FreeBASIC compiler
Compiler Option: -dylib	Create a DLL and import library.	Using the FreeBASIC compiler
Compiler Option: -e	Add error checking.	Using the FreeBASIC compiler
Compiler Option: -earray	Enable array bounds checking.	Using the FreeBASIC compiler
Compiler Option: -earraydims	Enable array dimensions checking.	Using the FreeBASIC compiler
Compiler Option: -eassert	Enable assert() and assertwarn() checking.	Using the FreeBASIC compiler
Compiler Option: -edebug	Enable __FB_DEBUG__.	Using the FreeBASIC compiler
Compiler Option: -edebuginfo	Add debug information.	Using the FreeBASIC compiler
Compiler Option: -elocation	Enable full error location reporting.	Using the FreeBASIC compiler
Compiler Option: -entry	Override the public exported name of the implicit user main function.	Using the FreeBASIC compiler
Compiler Option: -enullptr	Enable null-pointer checking.	Using the FreeBASIC compiler
Compiler Option: -eunwind	Enable stack unwind information.	Using the FreeBASIC compiler
Compiler Option: -ex	Add error checking, the same as -e.	Using the FreeBASIC compiler
Compiler Option: -export	Export symbols for dynamic linkage.	Using the FreeBASIC compiler
Compiler Option: -exx	Add error checking with array bounds/dimensions and null-pointer checking, plus stack overflow checking with gas64 backend.	Using the FreeBASIC compiler
Compiler Option: -forcelang	Provides QuickBASIC or backward compatibility.	Using the FreeBASIC compiler
Compiler Option: -fpmode	Selects faster, less accurate or slower, more precise floating-point math.	Using the FreeBASIC compiler
Compiler Option: -fpu	Sets the math unit to be used for floating point arithmetic.	Using the FreeBASIC compiler
Compiler Option: -g	Add debug information, define __FB_DEBUG__, and enable asserts.	Using the FreeBASIC compiler
Compiler Option: -gen	Sets the backend code emitter.	Using the FreeBASIC compiler
Compiler Option: -i	Add a path to search for include files.	Using the FreeBASIC compiler
Compiler Option: -include	Include a header file on each source compiled.	Using the FreeBASIC compiler
Compiler Option: -l	Add a library file to the linker's list.	Using the FreeBASIC compiler
Compiler Option: -lang	Provides QuickBASIC or backward compatibility.	Using the FreeBASIC compiler
Compiler Option: -lib	Create a static library.	Using the FreeBASIC compiler
Compiler Option: -m	Main file without extension to indicate the main module.	Using the FreeBASIC compiler
Compiler Option: -map	Save the linking map to file name.	Using the FreeBASIC compiler
Compiler Option: -maxerr	Set maximum number of errors to report before aborting compilation.	Using the FreeBASIC compiler
Compiler Option: -mt	Link with thread-safe runtime library.	Using the FreeBASIC compiler
Compiler Option: -nocopylibs		Using the tiko compiler
Compiler Option: -nodeflibs	Do not include the default libraries.	Using the FreeBASIC compiler
Compiler Option: -noerrline	Do not show source line where error occurred.	Using the FreeBASIC compiler
Compiler Option: -nolib	Do not include specific library(s).	Using the FreeBASIC compiler
Compiler Option: -norpath		Using the tiko compiler
Compiler Option: -noobjinfo	Do not read/write compile-time info from/to .o and .a files.	Using the FreeBASIC compiler
Compiler Option: -nostrip	Do not strip symbol information from the output file.	Using the FreeBASIC compiler
Compiler Option: -O	Set the optimization level for GCC.	Using the FreeBASIC compiler
Compiler Option: -o	Set object file path/name.	Using the FreeBASIC compiler
Compiler Option: -p	Add a path to search for libraries.	Using the FreeBASIC compiler
Compiler Option: -pic	Generate position-independent code (non-x86 Unix shared libs)	Using the FreeBASIC compiler
Compiler Option: -pp	Emit the preprocessed input file only, do not compile.	Using the FreeBASIC compiler
Compiler Option: -prefix	Set the compiler prefix path.	Using the FreeBASIC compiler
Compiler Option: -print	Print out information.	Using the FreeBASIC compiler
Compiler Option: -profgen	Enable function profiling by selecting a specific profiler.	Using the FreeBASIC compiler
Compiler Option: -profile	Enable function profiling for gmon/gprof.	Using the FreeBASIC compiler
Compiler Option: -R	Preserve intermediate *.asm/*.c/*.ll file(s) generated by compilation.	Using the FreeBASIC compiler
Compiler Option: -r	Compile into *.asm/*.c/*.ll file(s) only, do not assemble or link.	Using the FreeBASIC compiler
Compiler Option: -RR	Preserve intermediate *.asm files generated by compilation.	Using the FreeBASIC compiler
Compiler Option: -rr	Compile into *.asm file(s) only, do not assemble or link.	Using the FreeBASIC compiler
Compiler Option: -s	Sets the executable subsystem.	Using the FreeBASIC compiler
Compiler Option: -showincludes	Display a tree of file names of #included files.	Using the FreeBASIC compiler
Compiler Option: -static	Prefer static libraries over dynamic ones when linking.	Using the FreeBASIC compiler
Compiler Option: -strip	Omit all symbol information from the output file.	Using the FreeBASIC compiler
Compiler Option: -sysroot	Add a path to search for libraries.	Using the FreeBASIC compiler
Compiler Option: -t	Set stack size in kilobytes.	Using the FreeBASIC compiler
Compiler Option: -target	Set the target platform for cross compilation.	Using the FreeBASIC compiler
Compiler Option: -v	Be verbose.	Using the FreeBASIC compiler
Compiler Option: -vec	Enables vector optimizations by the compiler.	Using the FreeBASIC compiler
Compiler Option: -version	Show compiler version.	Using the FreeBASIC compiler
Compiler Option: -w	Set minimum warning level.	Using the FreeBASIC compiler
Compiler Option: -Wa	Pass options to the assembler when using the assembly emitter (-gen gas).	Using the FreeBASIC compiler
Compiler Option: -Wc	Pass options to the C compiler when using the C emitter (-gen gcc).	Using the FreeBASIC compiler
Compiler Option: -Wl		Using the FreeBASIC compiler
Compiler Option: -x		Using the FreeBASIC compiler
Compiler Option: -z	Sets miscellaneous or experimental compiler options.	Using the FreeBASIC compiler
Compiler Option: @file	Read (additional) command-line options from the file.	Using the FreeBASIC compiler
Complex	Holds a complex number as two Doubles, re and im.	Math Library
Complex operators	Adds, subtracts, multiplies, divides, raises and compares complex numbers.	Math Library
CondBroadcast	Wakes every thread waiting on the condition.	Threading Support Functions
CondCreate	Creates a condition variable and returns its handle, or 0 on failure.	Threading Support Functions
CondDestroy	Destroys a condition variable once no thread is waiting on it.	Threading Support Functions
CondSignal	Wakes one thread waiting on the condition; the signal is lost if none is waiting.	Threading Support Functions
CondWait	Unlocks the mutex and waits for a signal, then locks the mutex again.	Threading Support Functions
COne	Returns the complex number 1.	Math Library
Conjugate	Returns the conjugate of a quaternion, the reverse rotation when it is normalised.	Math Library
Console Functions	Procedures that work with the console.	Console Functions
ConsoleSink	Holds a sink that writes to stderr or stdout, in colour only on a terminal.	Logging
Const	Non-modifiable variable declaration.	Variable Declarations
Const (Member)	Specifies that a member procedure is read only.	User Defined Types
Const (Qualifier)	Specifies that a data type or pointer data type is read only.	Standard Data Types
Constructor	Called automatically when a class or user defined type is created.	User Defined Types
Constructor (Module)	Specifies execution of a procedure before module-level code.	Procedures
Contains	Returns true if the text appears anywhere in the string.	String Library
Contains	Returns true if any element equals the value.	Array
Contains	Returns true if the key is present, without adding it.	Map
Contains	Returns true if the value is in the set.	Set
Context	Holds the background context, which is never cancelled and is the root of all others.	Goroutines and Channels
Continue	Control flow statement to continue next iteration of a loop.	Control Flow Statements
Control Flow Statements	Statements that direct the flow of program execution.	Control Flow Statements
Converting Data Types	Operators and procedures that convert between different types.	Converting Data Types
CopyDir	Copies a folder and everything in it; returns how many entries it created.	Filesystem
CopyFile	Copies a file; fails if the destination exists unless overwrite is true.	Filesystem
CopyOptions.CopySymlinksAsLinks	Chooses whether CopyDir copies a link as a link rather than its target; true by default.	Filesystem
CopyOptions.Overwrite	Chooses whether CopyDir replaces files already at the destination; false by default.	Filesystem
CopyOptions.PreservePermissions	Chooses whether CopyDir keeps permission bits or attributes; false by default.	Filesystem
CopyOptions.PreserveTimestamps	Chooses whether CopyDir keeps each file's times; false by default.	Filesystem
CopySign	Returns a number's size with the sign of a second number, zero's sign included.	Math Library
Correlation	Returns the Pearson correlation of two arrays, from -1 to 1.	Math Library
Cos	Returns the cosine of an angle in radians.	Mathematical Functions
Cosh	Returns the hyperbolic cosine of a number.	Math Library
Count	Returns the number of elements; the valid indices are 0 to Count minus 1.	Array
Count	Returns the number of entries; reading an absent key with m[ k ] adds one.	Map
Count	Returns the number of values in the set.	Set
Count	Returns the number of values in the list.	LinkedList
Count	Returns how much work is still outstanding, as a snapshot.	Goroutines and Channels
Count	Counts the elements in an array.	Math Library
Covariance	Returns the sample covariance of two arrays of the same length.	Math Library
CPolar	Builds a complex number from a modulus and an angle in radians.	Math Library
CPow	Raises a complex or real number to a complex or real power.	Math Library
CPtr	Converts a pointer or an integer to the given pointer type.	Converting Data Types
CpuClock.IsSupported	Returns true if the platform can report processor time.	Date and Time (Chrono)
CpuClock.ProcessKernelTime	Returns the processor time the OS has spent working on behalf of this process.	Date and Time (Chrono)
CpuClock.ProcessTime	Returns the processor time this process has used so far, user and kernel together.	Date and Time (Chrono)
CpuClock.ProcessUserTime	Returns the processor time this process has spent running its own code.	Date and Time (Chrono)
CpuClock.ThreadTime	Returns the processor time the calling thread has used, user and kernel together.	Date and Time (Chrono)
CReal	Returns the real part of a complex number.	Math Library
CreateDir	Creates one folder; fails if something is already there.	Filesystem
CreateDirAll	Creates a folder and any missing parents; succeeds if it already exists.	Filesystem
CreateHardLink	Gives an existing file a second name on the same volume.	Filesystem
CreateSymlink	Creates a symbolic link to a target; on Windows this usually needs privilege.	Filesystem
CreateTempDir	Creates a uniquely named temporary folder and returns its path; it is not deleted for you.	Filesystem
CreateTempFile	Creates a uniquely named temporary file and returns its path; it is not deleted for you.	Filesystem
CReciprocal	Returns one divided by a complex number; zero gives zero.	Math Library
Cross	Returns a Vec3 perpendicular to both inputs; swapping them flips its direction.	Math Library
CryptoBytes	Fills a buffer with secure random bytes from the operating system; false on failure.	Math Library
CryptoULongInt	Returns a secure random 64-bit value from the operating system.	Math Library
CSec	Returns the secant of a complex number, one over the cosine.	Math Library
CSech	Returns the hyperbolic secant of a complex number, one over its cosh.	Math Library
CSet	Builds a complex number from its real and imaginary parts.	Math Library
CSetImag	Sets the imaginary part of a complex variable in place.	Math Library
CSetReal	Sets the real part of a complex variable in place.	Math Library
CSgn	Returns a complex number scaled to modulus 1, or zero for zero.	Math Library
CShort	Converts a number or string to a Short, rounding to the nearest; no overflow check.	Converting Data Types
CSign	Converts an unsigned value to signed, so division and shifts treat it as signed.	Converting Data Types
CSin	Returns the sine of a complex number.	Math Library
CSinh	Returns the hyperbolic sine of a complex number.	Math Library
CSng	Converts a number or string to a Single.	Converting Data Types
CSqrt	Returns the principal square root of a complex number or of a negative real.	Math Library
CsrLin	Returns the row the cursor is on, counting from 1 at the top.	Console Functions
CSwap	Swaps the values of two complex variables.	Math Library
CTan	Returns the tangent of a complex number, finite even for a large imaginary part.	Math Library
CTanh	Returns the hyperbolic tangent of a complex number.	Math Library
CToString	Returns a complex number as text such as 3+4i that reads back exactly.	Math Library
CToStringPolar	Returns a complex number as polar text, such as 5 * exp(0.927i).	Math Library
CUByte	Converts a number or string to a UByte, rounding to the nearest; no overflow check.	Converting Data Types
CUInt	Converts a number or string to a UInteger, rounding to the nearest; no overflow check.	Converting Data Types
CULng	Converts a number or string to a 32-bit ULong, rounding to the nearest; no overflow check.	Converting Data Types
CULngInt	Converts a number or string to a 64-bit ULongInt, rounding to the nearest.	Converting Data Types
CUnsg	Converts a signed value to unsigned, so division and shifts treat it as unsigned.	Converting Data Types
CurDir	Returns the current folder.	Operating System Functions
Currency	Holds an exact amount with four decimal places, for money that needs no more.	Finance
CurrencyFromDouble	Converts a double to a Currency, rounded to four decimal places.	Finance
CurrencyFromInt	Returns a Currency of a whole number of units, exactly.	Finance
CurrencyFromParts	Returns a Currency from whole units and a ten-thousandths part, exactly.	Finance
CurrencyFromRaw	Returns a Currency from its stored integer, which is the amount times 10000.	Finance
CurrencyInvalid	Returns the Invalid Currency, which overflow also produces; it never equals anything.	Finance
CurrencyParse	Parses text into a Currency exactly; returns empty on bad input or over four places.	Finance
CurrentDir	Returns the program's current folder.	Filesystem
CurrentLocaleFormat	Returns a NumFormat holding this machine's decimal and thousands separators.	Math Library
CUShort	Converts a number or string to a UShort, rounding to the nearest; no overflow check.	Converting Data Types
Custom	Calls your own function for each pixel to combine source and destination in Put.	2D Drawing Functions
Cva_Arg	Macro to obtain the next argument from a variadic argument list object.	Procedures
Cva_Copy	Macro to initialize variadic argument list object variable from an already initialized variadic argument list object variable.	Procedures
Cva_End	Macro to clean-up a variadic argument list object variable.	Procedures
Cva_List	Variadic argument list object type.	Procedures
Cva_Start	Macro to initialize variadic argument list object variable.	Procedures
CVD	Reads a Double back from an 8-byte string.	String Functions
CVI	Reads an integer back from a string of its bytes.	String Functions
CVL	Reads a Long back from a 4-byte string.	String Functions
CVLongInt	Reads a LongInt back from an 8-byte string.	String Functions
CVS	Reads a Single back from a 4-byte string.	String Functions
CVShort	Reads a Short back from a 2-byte string.	String Functions
CZero	Returns the complex number 0.	Math Library

D

Name	What it does	Category
#define	Preprocessor directive to define a macro.	Preprocessor
$Dynamic	Metacommand to change the way arrays are allocated.	Array Functions
Data	Statement to store data at compile time.	Miscellaneous Keywords
Date	Returns today's date as text in the form mm-dd-yyyy.	Date and Time Functions
Date and Time Functions	Procedures that work with dates and time.	Date and Time Functions
DateAdd	Returns a date serial moved by a number of years, months, days, hours or other units.	Date and Time Functions
DateDiff	Counts the years, months, days or other units between two date serials.	Date and Time Functions
DatePart	Returns one part of a date serial, such as its year, quarter, week or hour.	Date and Time Functions
DateSerial	Returns the date serial for a year, month and day; out-of-range values roll over.	Date and Time Functions
DateTime	Creates a date-time from a year, month, day and optional time, or Invalid if none.	Date and Time (Chrono)
DateTime.AddCalendarDays	Returns the same clock time a number of days later, even across a DST change.	Date and Time (Chrono)
DateTime.AddCalendarMonths	Returns the same clock time some months later, clamping the day to the month's end.	Date and Time (Chrono)
DateTime.AddCalendarYears	Returns the same clock time some years later, with the UTC offset worked out again.	Date and Time (Chrono)
DateTime.AddDays	Returns the date-time moved by days of exactly 24 hours, fractions allowed.	Date and Time (Chrono)
DateTime.AddHours	Returns the date-time moved by a number of hours, fractions allowed.	Date and Time (Chrono)
DateTime.AddMilliseconds	Returns the date-time moved by a number of milliseconds, fractions allowed.	Date and Time (Chrono)
DateTime.AddMinutes	Returns the date-time moved by a number of minutes, fractions allowed.	Date and Time (Chrono)
DateTime.AddMonths	Returns the date-time moved by whole months, clamping the day to the month's end.	Date and Time (Chrono)
DateTime.AddSeconds	Returns the date-time moved by a number of seconds, fractions allowed.	Date and Time (Chrono)
DateTime.AddTicks	Returns the date-time moved by a number of 100 ns ticks.	Date and Time (Chrono)
DateTime.AddYears	Returns the date-time moved by whole years; 29 February becomes the 28th if needed.	Date and Time (Chrono)
DateTime.AssumeUtc	Returns the moment the date-time names if its clock reading is taken as UTC.	Date and Time (Chrono)
DateTime.Day	Returns the day of the month, starting at 1.	Date and Time (Chrono)
DateTime.DayOfWeek	Returns the day of the week, 1 for Monday to 7 for Sunday.	Date and Time (Chrono)
DateTime.DayOfYear	Returns the day of the year, starting at 1.	Date and Time (Chrono)
DateTime.DaysInMonth	Returns the number of days in a month of a given year.	Date and Time (Chrono)
DateTime.DaysInYear	Returns 365 or 366, the number of days in a year.	Date and Time (Chrono)
DateTime.EndOfDay	Returns the last tick of the same day, 23:59:59.9999999.	Date and Time (Chrono)
DateTime.EndOfMonth	Returns the last tick of the last day of the month.	Date and Time (Chrono)
DateTime.EndOfYear	Returns the last tick of 31 December of the same year.	Date and Time (Chrono)
DateTime.FileTime	Returns the date-time as a Windows FILETIME: 100 ns ticks since 1601-01-01.	Date and Time (Chrono)
DateTime.FromDate	Returns a date-time at midnight on the given date.	Date and Time (Chrono)
DateTime.FromDateTime	Returns a date-time that joins a date and a time of day.	Date and Time (Chrono)
DateTime.FromFileTime	Creates a UTC date-time from a Windows FILETIME.	Date and Time (Chrono)
DateTime.FromInstant	Returns the date-time a moment shows on a clock with the given UTC offset.	Date and Time (Chrono)
DateTime.FromJulianDay	Creates a date-time from a fractional Julian day.	Date and Time (Chrono)
DateTime.FromOleDate	Creates a date-time from an OLE automation date.	Date and Time (Chrono)
DateTime.FromSerial	Creates a date-time from a date serial, the days since 1899-12-30.	Date and Time (Chrono)
DateTime.GetDate	Returns the date part as a LocalDate, dropping the time and the offset.	Date and Time (Chrono)
DateTime.GetTimeOfDay	Returns the time-of-day part as a LocalTime.	Date and Time (Chrono)
DateTime.HasOffset	Returns true if the date-time carries a UTC offset.	Date and Time (Chrono)
DateTime.Hour	Returns the hour, 0 to 23.	Date and Time (Chrono)
DateTime.IsFirstDayOfMonth	Returns true if the date is the first day of its month.	Date and Time (Chrono)
DateTime.IsLastDayOfMonth	Returns true if the date is the last day of its month.	Date and Time (Chrono)
DateTime.IsLeapYear	Returns true if a year is a leap year under the full Gregorian rule.	Date and Time (Chrono)
DateTime.IsoWeek	Returns the ISO week number, 1 to 53; pair it with IsoWeekYear.	Date and Time (Chrono)
DateTime.IsoWeekYear	Returns the year the ISO week belongs to, which can differ from Year near New Year.	Date and Time (Chrono)
DateTime.IsUtc	Returns true if the offset is zero; a date-time with no offset is not UTC.	Date and Time (Chrono)
DateTime.JulianDay	Returns the Julian day, a fractional day count whose days start at noon.	Date and Time (Chrono)
DateTime.JulianDayNumber	Returns the whole Julian day number, without the fraction.	Date and Time (Chrono)
DateTime.Microsecond	Returns the microseconds within the second, the milliseconds included.	Date and Time (Chrono)
DateTime.Millisecond	Returns the milliseconds within the second, 0 to 999.	Date and Time (Chrono)
DateTime.Minute	Returns the minute, 0 to 59.	Date and Time (Chrono)
DateTime.Month	Returns the month, 1 to 12.	Date and Time (Chrono)
DateTime.MonthName	Returns a month's name in the user's language, or its abbreviation.	Date and Time (Chrono)
DateTime.NextWeekday	Returns the same time on the next given weekday, always strictly later.	Date and Time (Chrono)
DateTime.OffsetMinutes	Returns the UTC offset in minutes; check HasOffset first, as no offset reads 32767.	Date and Time (Chrono)
DateTime.OleDate	Returns the date-time as an OLE automation date, the number Excel and ADO use.	Date and Time (Chrono)
DateTime.ParseExact	Reads text laid out by a pattern such as "dd/MM/yyyy", or Invalid if it does not match.	Date and Time (Chrono)
DateTime.PrevWeekday	Returns the same time on the previous given weekday, always strictly earlier.	Date and Time (Chrono)
DateTime.Quarter	Returns the calendar quarter, 1 to 4.	Date and Time (Chrono)
DateTime.Second	Returns the second, 0 to 59.	Date and Time (Chrono)
DateTime.Serial	Returns the date-time as a date serial: days since 1899-12-30, with a fraction.	Date and Time (Chrono)
DateTime.StartOfDay	Returns midnight at the start of the same day, keeping the offset.	Date and Time (Chrono)
DateTime.StartOfMonth	Returns midnight on the first day of the month.	Date and Time (Chrono)
DateTime.StartOfWeek	Returns midnight on the first day of the week, Monday unless told otherwise.	Date and Time (Chrono)
DateTime.StartOfYear	Returns midnight on 1 January of the same year.	Date and Time (Chrono)
DateTime.TickOfDay	Returns the time of day as one number: 100 ns ticks since midnight.	Date and Time (Chrono)
DateTime.ToInstant	Returns the moment the date-time names, or Invalid if it has no offset.	Date and Time (Chrono)
DateTime.ToLocal	Returns the same moment shown at the machine's local UTC offset.	Date and Time (Chrono)
DateTime.ToLocaleDateString	Returns the date as the machine's locale writes it, for display only.	Date and Time (Chrono)
DateTime.ToLocaleString	Returns the date and time as the machine's locale writes them, for display only.	Date and Time (Chrono)
DateTime.ToLocaleTimeString	Returns the time of day as the machine's locale writes it, for display only.	Date and Time (Chrono)
DateTime.ToOffset	Converts to another UTC offset, keeping the moment and changing the clock reading.	Date and Time (Chrono)
DateTime.TryFormat	Formats the date-time with a pattern into a variable; returns false if the pattern is bad.	Date and Time (Chrono)
DateTime.TryParse	Reads ISO 8601 text into a date-time, the same as TryParseIso.	Date and Time (Chrono)
DateTime.TryParseExact	Reads text laid out by a pattern into a date-time; returns false if it does not match.	Date and Time (Chrono)
DateTime.WeekdayName	Returns a weekday's name in the user's language, 1 being Monday, or its abbreviation.	Date and Time (Chrono)
DateTime.WeeksInYear	Returns 52 or 53, the number of ISO weeks in a year.	Date and Time (Chrono)
DateTime.WithOffset	Attaches a UTC offset in minutes, keeping the clock reading and changing the moment.	Date and Time (Chrono)
DateTime.Year	Returns the year, 1 to 9999.	Date and Time (Chrono)
DateValue	Returns the date serial for text written in the system's date format.	Date and Time Functions
Day	Returns the day of the month of a date serial.	Date and Time Functions
Deallocate	Frees memory from Allocate, CAllocate or Reallocate; does nothing for a null pointer.	Memory Functions
Debug	Logs a message at the debug level, or returns a record to add fields to.	Logging
Debugging		Using the FreeBASIC compiler
Decimal	Holds an exact decimal number with up to 28 places, for rates, prices and results.	Finance
DecimalApportion	Splits a Decimal total by weights, at a scale you choose, into parts that add up exactly.	Finance
DecimalCompare	Returns -1, 0 or 1 comparing two Decimals by value, or -2 if either is Invalid.	Finance
DecimalFromCurrency	Converts a Currency to a Decimal, exactly.	Finance
DecimalFromDouble	Converts a double to a Decimal of 15 significant digits; NaN or infinity gives Invalid.	Finance
DecimalFromInt	Returns a 64-bit integer as a Decimal, exactly.	Finance
DecimalFromParts	Builds a Decimal from three 32-bit mantissa words, a sign flag and a scale.	Finance
DecimalFromScaled	Returns a whole number over a power of ten as a Decimal: 1999 at scale 2 is 19.99.	Finance
DecimalFromUInt	Returns an unsigned 64-bit integer as a Decimal, exactly.	Finance
DecimalInvalid	Returns the Invalid Decimal, which overflow and division by zero also produce.	Finance
DecimalMaxValue	Returns the largest value a Decimal can hold.	Finance
DecimalMinusOne	Returns minus one as a Decimal.	Finance
DecimalMinValue	Returns the most negative value a Decimal can hold.	Finance
DecimalOne	Returns one as a Decimal.	Finance
DecimalParse	Parses text into a Decimal exactly; returns empty on bad input or over 28 places.	Finance
DecimalZero	Returns zero, the same value a new Decimal starts with.	Finance
Declare	Declares a module-level or member procedure.	Procedures
Default Palettes	Default color values for FreeBASIC graphics and text screen modes.	Graphics Library Reference
Defer		Defer
defined	Preprocessor function to test if a symbol has been defined.	Preprocessor
DegToRad	Converts an angle from degrees to radians.	Math Library
DeleteAt	Deletes a number of characters at a position.	String Library
Destructor	Called automatically when a class or user defined type goes out of scope or is destroyed.	User Defined Types
Destructor (Module)	Specifies execution of a procedure at program termination.	Procedures
Determinant	Returns the determinant of a matrix; zero means it has no inverse.	Math Library
Dim	Declares a variable.	Variable Declarations
Dir	Returns the first name matching a pattern, then the next one on each later call.	Operating System Functions
DirEntry.Depth	Returns how deep the entry is in a walk, 0 for the children of the folder walked.	Filesystem
DirEntry.Info	Returns the entry's FileInfo: free on Windows, one extra system call on Linux and macOS.	Filesystem
DirEntry.IsDirectory	Returns true if the entry is a folder; a link to a folder reports as a link.	Filesystem
DirEntry.IsFile	Returns true if the entry is a file; a link reports as a link, not as its target.	Filesystem
DirEntry.IsOther	Returns true if the entry is a device, pipe or socket rather than a file, folder or link.	Filesystem
DirEntry.IsSymlink	Returns true if the entry is a symbolic link.	Filesystem
DirEntry.Name	Returns the entry's name, without its folder.	Filesystem
DirEntry.Path	Returns the entry's full path, ready to open.	Filesystem
DirIterator	Holds the iterator ReadDir hands out, for stepping through a folder without for each.	Filesystem
DirIterator.IsValid	Returns true while the iterator is on an entry.	Filesystem
DirIterator.MoveNext	Moves the iterator on to the next entry.	Filesystem
DirIterator.Value	Returns the current entry by reference; the next MoveNext makes it invalid.	Filesystem
DiskSpace.AvailableBytes	Returns the bytes this user may still write; the number to check before writing.	Filesystem
DiskSpace.FreeBytes	Returns the free bytes on the volume, ignoring quotas; the number to report.	Filesystem
DiskSpace.TotalBytes	Returns the capacity of the volume in bytes.	Filesystem
Distance	Returns the distance between two points.	Math Library
DistanceSquared	Returns the squared distance between two points, the cheap way to test a range.	Math Library
DivChecked	Divides two integers, returning an empty Optional on division by zero or overflow.	Math Library
DivMod	Returns the quotient and the remainder of one division together, as a tuple.	Math Library
Do	Control flow statement for looping.	Miscellaneous Keywords
Do...Loop	Control flow statement for looping.	Control Flow Statements
Done	Subtracts one from the work outstanding; raises an error if it would go below zero.	Goroutines and Channels
DOS Keyboard Scancodes	Listing of keyboard scancodes.	Graphics Library Reference
Dot	Returns the dot product of two vectors; zero means they are perpendicular.	Math Library
Double	Standard data type: 64 bit floating point.	Mathematical Functions
Draw	Draws a figure from a string of pen commands such as "U10 R10".	Screen Functions
Draw String	Draws text at a pixel position, on a transparent background, with an optional font.	2D Drawing Functions
DyLibFree	Unloads a dynamic link library from memory.	Modularizing
DyLibLoad	Loads to a Dynamic Link Library (DLL) into memory at runtime.	Modularizing
DyLibSymbol	Returns the address of a function or variable in a dll.	Modularizing

E

Name	What it does	Category
#else	Preprocessor conditional directive.	Preprocessor
#elseif	Preprocessor conditional directive.	Preprocessor
#elseifdef	Preprocessor conditional directive.	Preprocessor
#elseifndef	Preprocessor conditional directive.	Preprocessor
#endif	Preprocessor conditional directive.	Preprocessor
#error	Preprocessor diagnostic directive.	Preprocessor
Else	Control flow statement for conditional branching.	Control Flow Statements
ElseIf	Control flow statement for conditional branching.	Control Flow Statements
Emit	Sends a finished record straight to every attached sink.	Logging
Enabled	Returns true if a record at a level would be emitted, to skip building costly messages.	Logging
Encoding	Sets the Unicode encoding of a text file in Open; a file read this way needs a BOM.	File I/O Functions
End (Block)	Indicates the end of a compound statement block.	Miscellaneous Keywords
End (Statement)	Control flow statement to end the program.	Miscellaneous Keywords
End If	Control flow statement for conditional branching.	Miscellaneous Keywords
EndsWith	Returns true if the string ends with the given text.	String Library
Enum	Declares an enumerated type.	User Defined Types
Environ	Returns the value of an environment variable, or an empty string if it is not set.	Operating System Functions
EOF	Returns true when an open file has nothing left to read.	File I/O Functions
Equals	Returns true if two slices hold the same code units, optionally ignoring case.	String Slices
Erase	Frees a variable-length array's elements, or resets those of a fixed-length array.	Array Functions
Erfn	Returns a pointer to the name of the failing procedure; null unless built with -exx.	Error Handling Functions
Erl	Returns the source line of the last runtime error, or 0 if there was none.	Error Handling Functions
Ermn	Returns a pointer to the name of the source file where the last error happened.	Error Handling Functions
Err	Returns the number of the last runtime error, or sets it without jumping.	Error Handling Functions
Err	Returns why the context ended: "cancelled", "deadline exceeded", or "" while live.	Goroutines and Channels
Error	Raises a runtime error by number: jumps to the handler, or ends the program.	Error Handling Functions
Error	Logs a message at the error level, or returns a record to add fields to.	Logging
Error Handling	Handling runtime errors.	Language Documentation
Error Handling Functions	Statements and procedures that provide runtime error-handling capabilities.	Error Handling Functions
Escape	Replaces quotes, backslashes and control characters with backslash escapes.	String Library
Escape Sequences	Escape sequences can be used in string literals by using the operator ! .	Language Documentation
EuclidDiv	Divides whole numbers so that the matching EuclidMod remainder is never negative.	Math Library
EuclidMod	Returns a remainder that is never negative, whatever the signs.	Math Library
Event (Message Data From Screenevent)	Holds one event fetched by ScreenEvent: its type and its key or mouse data.	Screen Functions
ExceptWith	Removes every value that is also in another set.	Set
Exec	Runs a program by its path with arguments, waits, and returns its exit code or -1.	Operating System Functions
ExePath	Returns the folder that holds the running program.	Operating System Functions
Exists	Returns true if a file or folder is there; false also when access is denied.	Filesystem
Exit	Control flow statement to exit a compound statement block.	Control Flow Statements
Exp	Returns e raised to a power.	Mathematical Functions
Exp2	Returns 2 raised to a power.	Math Library
Expired	Returns true once the object has been destroyed.	Smart Pointers
Expm1	Returns e raised to a power, minus one, accurately for powers near zero.	Math Library
Export	Definition specifier to indicate that a procedure in a DLL should be visible from other programs.	Modularizing
Extends	Specifies a base type from which to derive a new type.	User Defined Types
Extends Wstring	Specifies a type which inherits a Wstring behavior.	User Defined Types
Extends Zstring	Specifies a type which inherits a Zstring behavior.	User Defined Types
Extern	Declares a variable, array or object having external linkage.	Modularizing
Extern...End Extern	Statement block to allow calling of functions compiled for specific languages or platforms.	Modularizing
Extract	Returns the text before a match, or the whole rest if there is none.	String Library
ExtractChars	Returns the text before the first character from a set.	String Library

F

Name	What it does	Category
Fail	Returns a failed Result holding the reason; both types must be written out.	Result
Failure	Returns the reason by reference; raises an error if the Result succeeded.	Result
False	Intrinsic constant set by the compiler.	Intrinsic Defines
Fatal	Logs a message at the most severe level, or returns a record; it does not end the program.	Logging
Fb_Memcopy	Copies a number of bytes between two memory areas that do not overlap.	Memory Functions
fb_MemCopyClear	Copies the first bytes of one area into another and sets the rest to zero.	Memory Functions
Fb_Memmove	Copies a number of bytes between two memory areas, even when they overlap.	Memory Functions
Fbarray (Array Descriptor Structure And Access)	Holds an array's descriptor: its bounds, sizes and data pointers.	Array Functions
Field	Specifies field alignment.	User Defined Types
File I/O Functions	Statements and procedures for working with files and devices.	File I/O Functions
FileAttr	Returns an open file number's mode, system handle or encoding.	Operating System Functions
FileCopy	Copies a file, overwriting the destination; returns 0 on success.	Operating System Functions
FileDateTime	Returns when a file was last modified, as a date serial.	Operating System Functions
FileExists	Returns non-zero if the file exists, or 0 if it does not.	Operating System Functions
FileFlush	Writes buffered output for one or all open files to the system, or on to disk.	Operating System Functions
FileInfo.AccessedUtc	Returns the last-access time in ticks, or 0 when HasAccessed is false.	Filesystem
FileInfo.CreatedUtc	Returns the creation time in ticks, or 0 when HasCreated is false.	Filesystem
FileInfo.Exists	Returns true if the FileInfo describes something that exists.	Filesystem
FileInfo.HasAccessed	Returns true if the platform records access times, so Accessed means something.	Filesystem
FileInfo.HasCreated	Returns true if the platform records creation times, so Created means something.	Filesystem
FileInfo.IsDirectory	Returns true if the path is a folder.	Filesystem
FileInfo.IsFile	Returns true if the path is a regular file.	Filesystem
FileInfo.IsHidden	Returns true if hidden: the hidden flag on Windows, a leading dot on Linux and macOS.	Filesystem
FileInfo.IsOther	Returns true if the path is a device, pipe or socket rather than a file, folder or link.	Filesystem
FileInfo.IsReadOnly	Returns true if unwritable: the read-only flag, or no write bit on Linux and macOS.	Filesystem
FileInfo.IsSymlink	Returns true if the path is a symbolic link; only ever true from LStat.	Filesystem
FileInfo.ModifiedUtc	Returns the last-write time in ticks of 100 ns since 0001-01-01 UTC.	Filesystem
FileInfo.NativeAttributes	Returns the raw attribute word: attributes on Windows, mode bits on Linux and macOS.	Filesystem
FileInfo.NativeAttributes	Returns the raw attribute word: attributes on Windows, mode bits on Linux and macOS.	Filesystem
FileInfo.Size	Returns the size in bytes.	Filesystem
FileLen	Returns the size of a named file in bytes.	Operating System Functions
FileLock.Acquire	Takes a lock on a file that cooperating programs share, waiting up to a timeout.	Filesystem
FileLock.IsHeld	Returns true while this FileLock holds its lock.	Filesystem
FileLock.Release	Releases the lock; harmless when none is held.	Filesystem
FileSetEof	Cuts or extends an open file so that it ends at the current position.	Operating System Functions
Filesystem Library		Filesystem
FileWatcher.IsWatching	Returns true while the watcher is running.	Filesystem
FileWatcher.Poll	Fills an Array with the changes seen since the last call, waiting up to a timeout.	Filesystem
FileWatcher.Start	Starts watching a folder for changes, subfolders too when recursive is true.	Filesystem
FileWatcher.Stop	Stops watching; harmless when not watching.	Filesystem
Find	Returns the position of the first match in a slice, counting from 0, or -1.	String Slices
Fix	Returns the whole-number part, rounding towards zero, so Fix(-4.9) is -4.	Mathematical Functions
Fixed-Width Types		Fixed-Width Types
Flip	Shows the OpenGL back buffer, or copies a page as ScreenCopy does in other modes.	Screen Functions
Float32		Fixed-Width Types
Float64		Fixed-Width Types
Floor	Rounds down, towards negative infinity, so Floor(-2.1) is -3.	Math Library
FloorDiv	Divides whole numbers rounding towards negative infinity, so FloorDiv(-7, 2) is -4.	Math Library
FloorMod	Returns the remainder with the divisor's sign, so FloorMod(-1, 5) is 4.	Math Library
Flush	Flushes every sink attached to the logger.	Logging
Fma	Returns x * y + z with a single rounding at the end.	Math Library
For	Control flow statement, open statement clause, or operator depending on context.	Miscellaneous Keywords
For Each		For Each
For...Next	Control flow statement for looping.	Operators
ForEach	Calls a procedure on every element in order, passing each by reference.	Array
#cinclude		C Header Import
#cinclude Tutorial		C Header Import
C Header Import		C Header Import
#foreignlib		Foreign Library Linking
#foreignlib Tutorial		Foreign Library Linking
Foreign Library Linking		Foreign Library Linking
Format	Formats a number with a picture string such as "#,##0.00".	String Functions
Frac	Returns the fractional part, keeping the sign, so Frac(-1.75) is -0.75.	Mathematical Functions
Fre	Returns the amount of free physical memory, in bytes.	Operating System Functions
FreeFile	Returns an unused file number for Open, or 0 if all 255 are taken.	File I/O Functions
Frexp	Splits a number into a fraction from 0.5 to 1 and a power of two.	Math Library
Front	Returns a reference to the front value without removing it.	LinkedList
FsChange.Kind	Returns what happened: created, deleted, modified, renamed, or overflow.	Filesystem
FsChange.Path	Returns the full path of the entry that changed.	Filesystem
FsError.Code	Returns the portable error code, such as FS_NOT_FOUND, to branch on.	Filesystem
FsError.Message	Returns a fixed one-line description of the error code.	Filesystem
FsError.Operation	Returns the name of the call that failed, for diagnostics only.	Filesystem
FsError.OsCode	Returns the operating system's own error number, or 0 if the library raised the error.	Filesystem
FsError.Path	Returns the path the failed call was working on, or an empty string.	Filesystem
FsError.Path2	Returns the second path of a failed copy, move or link call.	Filesystem
Function	Defines a procedure returning a value.	Procedures
Function (Member)	Declares or defines a member procedure returning a value.	User Defined Types
Function Pointer	Data type that stores a pointer to a Function procedure returning a value.	Standard Data Types
Functional Keyword List	List of FreeBASIC keywords sorted by the function they perform.	Language Documentation

G

Name	What it does	Category
GCD	Returns the greatest common divisor of two whole numbers.	Math Library
Generics		Generics
Get	Returns the raw pointer to the object, or 0 if null, without adding an owner.	Smart Pointers
Get (File I/O)	Reads a variable, string or array from a file as bytes, at a position or the current one.	File I/O Functions
Get (Graphics)	Copies a rectangle of the screen or an image into an image buffer.	2D Drawing Functions
GetDiskSpace	Returns the total, free and available bytes of the volume a path is on.	Filesystem
GetIterator		For Each
GetIterator	Returns an iterator over the elements, for stepping through them by hand.	Array
GetIterator	Returns an iterator over the entries, each a pair read through .key and .value.	Map
GetIterator	Returns an iterator over the values, in no particular order.	Set
GetIterator	Returns an iterator over the values that stays valid when others are added.	LinkedList
GetJoystick	Fills in a joystick's buttons and axis positions; returns 0 on success or 1.	User Input Functions (Graphics Library)
GetKey	Waits for a key and returns its code; the key is not shown on screen.	User Input (Runtime Library)
GetMouse	Fills in the mouse position, wheel and buttons, or -1 in each if there is no mouse.	User Input Functions (Graphics Library)
GetPosixMode	Returns a file's permission bits on Linux and macOS; fails as unsupported on Windows.	Filesystem
GetRoundingMode	Returns the direction floating-point results are currently rounded in.	Math Library
GetVolumeInfo	Returns the VolumeInfo of the volume a path is on: its root, label and file system.	Filesystem
GetVolumes	Fills an Array with a VolumeInfo for each drive or mounted disk; returns the count.	Filesystem
GetWin32Attributes	Returns a file's raw Windows attribute flags; fails as unsupported on Linux and macOS.	Filesystem
GfxLib - FreeBASIC graphics library overview		Graphics Library Reference
Glob	Fills an Array with the paths that match a wildcard pattern; returns the count.	Filesystem
GlobRoot	Returns the folder a pattern search starts from: the part before the first wildcard.	Filesystem
GoroutineCount	Returns how many goroutines exist right now, as a snapshot for diagnostics.	Goroutines and Channels
Goroutines and Channels		Goroutines and Channels
Goroutines Tutorial		Goroutines and Channels
GoSub	Control flow statement to use a section of code and return.	Control Flow Statements
Goto	Control flow statement to jump to another part of the program.	Control Flow Statements
Graphics Keyword List	A list of the keywords and procedures of FreeBASIC's graphics library.	Graphics Keyword List

H

Name	What it does	Category
HasValue	Returns true if the Optional holds a value.	Optional
Hex	Returns a number as hexadecimal text.	String Functions
HiByte	Returns the second byte of a number, bits 8 to 15.	Bit Manipulation
HiWord	Returns bits 16 to 31 of a number.	Bit Manipulation
Hour	Returns the hour of a date serial, 0 to 23.	Date and Time Functions
Hypot	Returns the square root of xx + yy without overflowing for large values.	Math Library

I

Name	What it does	Category
#if	Preprocessor conditional directive.	Preprocessor
#ifdef	Preprocessor conditional directive.	Preprocessor
#ifndef	Preprocessor conditional directive.	Preprocessor
#inclib	Preprocessor directive.	Preprocessor
#include	Preprocessor statement to include contents of another source file.	Preprocessor
If...Then	Control flow statement for conditional branching.	Control Flow Statements
IIf	Conditional function that returns one of two values.	Miscellaneous Keywords
ImageConvertRow	Copies a row of pixels to another buffer, converting its colour depth.	2D Drawing Functions
ImageCreate	Creates an image of a given size filled with one colour; returns 0 on failure.	2D Drawing Functions
ImageDestroy	Frees an image made by ImageCreate.	2D Drawing Functions
ImageInfo	Fills in an image's width, height, bytes per pixel, pitch and pixel pointer.	2D Drawing Functions
Implements	Lists the interfaces a type or class takes on, and says which interface member each method provides.	Interfaces
Import	External linkage attribute for public data located in DLL's.	Modularizing
Indexing Operators	Operators that return references based on an index.	Operators
IndexOf	Returns the index of the first element equal to a value, or -1 if there is none.	Array
Infinity	Returns positive infinity as a Double.	Math Library
InfinityF	Returns positive infinity as a Single.	Math Library
Info	Logs a message at the info level, or returns a record to add fields to.	Logging
Inherits	Names a class's base class, or the interfaces an interface includes.	Interfaces
Inkey	Returns the next key waiting, or an empty string at once if there is none.	User Input (Runtime Library)
Inp	Returns a value at a hardware port.	Miscellaneous Keywords
Input	Reads values the user types, up to Enter, after an optional prompt.	User Input (Runtime Library)
Input #	Reads comma- or line-separated values from a text file into variables.	File I/O Functions
Input (File Mode)	Opens a text file for reading with Open; the file must already exist.	File I/O Functions
Input()	Waits for a number of characters from the keyboard or a file and returns them.	User Input (Runtime Library)
Insert	Inserts a value at a position, moving the later elements up one place.	Array
InsertAt	Inserts text at a position.	String Library
Instant.Add	Returns the date-time moved forward by a TimeSpan.	Date and Time (Chrono)
Instant.CompareTo	Returns -1, 0 or 1 to order two moments, or -2 if either is Invalid.	Date and Time (Chrono)
Instant.FromTicks	Creates a moment from 100 ns ticks since 0001-01-01, or Invalid if out of range.	Date and Time (Chrono)
Instant.FromUnixMicroseconds	Returns the moment a number of microseconds after 1970-01-01 UTC.	Date and Time (Chrono)
Instant.FromUnixMilliseconds	Returns the moment a number of milliseconds after 1970-01-01 UTC.	Date and Time (Chrono)
Instant.FromUnixSeconds	Returns the moment a number of seconds after 1970-01-01 UTC; negative is earlier.	Date and Time (Chrono)
Instant.Instant	Creates a moment on the UTC timeline from a tick count; Invalid with no argument.	Date and Time (Chrono)
Instant.Invalid	Returns the Invalid date-time, which never equals anything, itself included.	Date and Time (Chrono)
Instant.IsValid	Returns true if the date-time is a real, in-range value; the only safe test.	Date and Time (Chrono)
Instant.MaxValue	Returns the latest date-time, the last tick of 9999-12-31.	Date and Time (Chrono)
Instant.MinValue	Returns the earliest date-time, midnight on 0001-01-01.	Date and Time (Chrono)
Instant.ParseIso	Reads ISO 8601 text into a date-time, or Invalid if it is not ISO 8601.	Date and Time (Chrono)
Instant.Subtract	Returns the date-time moved back by a TimeSpan, or Invalid past the earliest date.	Date and Time (Chrono)
Instant.Ticks	Returns the 100 ns ticks since 0001-01-01, counted on the value's own clock.	Date and Time (Chrono)
Instant.ToIsoString	Returns the date-time as ISO 8601 text, with Z or the offset when it has one.	Date and Time (Chrono)
Instant.ToString	Returns ISO 8601 text, or the date-time laid out by a pattern such as "yyyy-MM-dd".	Date and Time (Chrono)
Instant.TryParseIso	Reads ISO 8601 text into a date-time; returns false and sets it Invalid on failure.	Date and Time (Chrono)
Instant.UnixMicroseconds	Returns the microseconds since 1970-01-01 UTC.	Date and Time (Chrono)
Instant.UnixMilliseconds	Returns the milliseconds since 1970-01-01 UTC.	Date and Time (Chrono)
Instant.UnixSeconds	Returns the whole seconds since 1970-01-01 UTC, dropping any fraction.	Date and Time (Chrono)
InStr	Returns the position of the first match, or 0 if there is none.	String Functions
InstrChars	Returns the position of the first character from a set, or 0.	String Library
InStrRev	Returns the position of the last match, or 0 if there is none.	String Functions
Int	Returns the largest whole number not above the value, so Int(-1.3) is -2.	Mathematical Functions
Int16		Fixed-Width Types
Int32		Fixed-Width Types
Int64		Fixed-Width Types
Int8		Fixed-Width Types
Integer	Standard data type: 32-bit or 64-bit signed, same size as SizeOf(Any Ptr)	Standard Data Types
Interface	Declares a contract: a list of methods and properties that a type promises to provide.	Interfaces
IntersectWith	Keeps only the values that are also in another set.	Set
Intrinsic Defines	Preprocessor symbols defined by the compiler.	Intrinsic Defines
IPow	Raises a whole number to a whole-number power exactly, with no trip through Double.	Math Library
IPowChecked	Raises an integer to a power, returning an empty Optional if the result overflows.	Math Library
Is	Clause in the Select Case statement block.	Miscellaneous Keywords
IsBlank	Returns true if the string is empty or holds only whitespace.	String Library
IsCancelled	Returns true once the context is cancelled or its deadline has passed.	Goroutines and Channels
IsDate	Returns true if the text can be read as a date in the system's date format.	Date and Time Functions
IsDir	Returns true if the path is a folder, following links; false if it cannot tell.	Filesystem
IsEmpty	Returns true if the array has no elements.	Array
IsEmpty	Returns true if the map has no entries.	Map
IsEmpty	Returns true if the set has no values.	Set
IsEmpty	Returns true if the list has no values.	LinkedList
IsFile	Returns true if the path is a file, following links; false if it cannot tell.	Filesystem
IsFinite	Returns true if the value is neither infinite nor NaN.	Math Library
IsInfinite	Returns true if the value is plus or minus infinity.	Math Library
IsLink	Returns true if the path itself is a symbolic link.	Filesystem
IsNaN	Returns true if the value is NaN, which an equality test cannot detect.	Math Library
IsNegative	Returns true if the sign bit is set, which includes negative zero.	Math Library
IsNormal	Returns true if the value is finite, not zero and not subnormal.	Math Library
IsNull	Returns true if the handle owns no object.	Smart Pointers
IsNumeric	Returns true if the string is a valid number, with spaces allowed around it.	String Library
IsOk	Returns true if the Result holds a value rather than a reason for failure.	Result
IsPow2	Returns true if the value is a power of two; zero is not one.	Math Library
ISqrt	Returns the exact whole-number square root, rounded down.	Math Library
IsRedirected	Returns non-zero if standard output, or input if asked, is redirected to a file.	Operating System Functions
IsSorted	Returns true if the Array is already in ascending order.	Array
IsSorted	Returns true if the Array is already in ascending order.	Sorting
IsSortedBy	Returns true if the Array is already in order by your comparer.	Sorting
IsSubnormal	Returns true if the value is nonzero but below the smallest normal number.	Math Library
IsValid		For Each
IsValid	Returns false if the Currency is Invalid; the only reliable test for a bad value.	Finance
Items	Returns a copy of all the values as an Array, in no particular order.	Set
Iterating Operators	Operators that work with iterator objects.	Operators
Iterator Protocol		Iterators

J

Name	What it does	Category
Join	Joins an Array of strings into one, with a separator between them.	String Library

K

Name	What it does	Category
Keys	Returns a copy of all the keys as an Array, in no particular order.	Map
Kill	Deletes a file; returns 0 on success or an error code.	Operating System Functions

L

Name	What it does	Category
#lang	Preprocessor statement to set the compiler dialect.	Preprocessor
#libpath	Preprocessor statement to add a search path for libraries.	Preprocessor
#line	Preprocessor directive to set the current line number and file name.	Preprocessor
Lambdas		Lambdas
LBound	Returns the lowest valid index of an array dimension, or 0 if there is none.	Array Functions
LCase	Returns a lower-case copy of the string.	String Functions
LCM	Returns the least common multiple of two whole numbers, or 0 if either is 0.	Math Library
LeadingZeros	Counts the zero bits above the highest set bit; zero gives the type's full width.	Math Library
Left	Returns the first n characters.	String Functions
Len	Returns the length of a string, or the size of a type.	String Functions
Length	Returns the length of a vector.	Math Library
LengthSquared	Returns the squared length of a vector, the cheap way to compare lengths.	Math Library
Lerp	Returns the point a fraction t of the way from a to b; t is not clamped.	Math Library
Let	Indicates the assignment operator.	Miscellaneous Keywords
LevelFromName	Reads a level from a name or number in any case; returns false if it is unknown.	Logging
LevelName	Returns a level's name, such as "WARN", or its number if it has no name.	Logging
LevelNameShort	Returns a level's three-letter name, such as "WRN".	Logging
LevelToSyslog	Returns the syslog severity number for a level.	Logging
Lib	Specifies the library where a sub or function can be found as part of a declaration.	Procedures
Line (Graphics)	Draws a line between two points, or a box or filled box with B or BF.	2D Drawing Functions
Line Input	Reads a whole typed line into a string, commas included, after an optional prompt.	User Input (Runtime Library)
Line Input #	Reads one line of a text file into a string, without its line ending.	File I/O Functions
LinkCount	Returns how many hard links, or names, a file has.	Filesystem
LinkedList		LinkedList
LinkedList	Holds a chain of values that is quick to add to and remove from at either end.	LinkedList
LinkedListIterator	Holds a position in a LinkedList; it survives changes elsewhere in the list.	LinkedList
LinkedNode	Holds one LinkedList value and the links to its neighbours; normal code never uses it.	LinkedList
ListDir	Fills an Array with one folder's entries at once; returns the count.	Filesystem
Literals	Non-variable compile-time string, numeric values and boolean values.	Language Documentation
LLVM Backend		LLVM Backend
LoByte	Returns the lowest byte of a number, bits 0 to 7.	Bit Manipulation
LOC	Returns where the last read or write happened in an open file, counted in records.	File I/O Functions
Local	Marks an On Error handler as belonging to the procedure it is set in.	Error Handling Functions
LocalDate.AddDays	Returns the date moved by a number of days.	Date and Time (Chrono)
LocalDate.AddMonths	Returns the date moved by whole months, clamping the day to the month's end.	Date and Time (Chrono)
LocalDate.AddYears	Returns the date moved by whole years; 29 February becomes the 28th if needed.	Date and Time (Chrono)
LocalDate.CompareTo	Returns -1, 0 or 1 to order two dates, or -2 if either is Invalid.	Date and Time (Chrono)
LocalDate.Day	Returns the day of the month, starting at 1.	Date and Time (Chrono)
LocalDate.DayNumber	Returns the days since 0001-01-01; subtract two to count the days between dates.	Date and Time (Chrono)
LocalDate.DayOfWeek	Returns the day of the week, 1 for Monday to 7 for Sunday.	Date and Time (Chrono)
LocalDate.DayOfYear	Returns the day of the year, starting at 1.	Date and Time (Chrono)
LocalDate.EndOfMonth	Returns the last day of the date's month.	Date and Time (Chrono)
LocalDate.FromDayNumber	Creates a date from a count of days since 0001-01-01.	Date and Time (Chrono)
LocalDate.Invalid	Returns the Invalid date, which spreads to anything computed from it.	Date and Time (Chrono)
LocalDate.IsFirstDayOfMonth	Returns true if the date is the first day of its month.	Date and Time (Chrono)
LocalDate.IsLastDayOfMonth	Returns true if the date is the last day of its month.	Date and Time (Chrono)
LocalDate.IsoWeek	Returns the ISO week number, 1 to 53; pair it with IsoWeekYear.	Date and Time (Chrono)
LocalDate.IsoWeekYear	Returns the year the ISO week belongs to, which can differ from Year near New Year.	Date and Time (Chrono)
LocalDate.IsValid	Returns true if the date exists and is in range.	Date and Time (Chrono)
LocalDate.LocalDate	Creates a date with no time of day from a year, month and day, or Invalid if none.	Date and Time (Chrono)
LocalDate.MaxValue	Returns the latest date, 9999-12-31.	Date and Time (Chrono)
LocalDate.MinValue	Returns the earliest date, 0001-01-01.	Date and Time (Chrono)
LocalDate.Month	Returns the month, 1 to 12.	Date and Time (Chrono)
LocalDate.ParseIso	Reads ISO text such as 2026-08-13 into a date, or Invalid on failure.	Date and Time (Chrono)
LocalDate.Quarter	Returns the calendar quarter, 1 to 4.	Date and Time (Chrono)
LocalDate.StartOfMonth	Returns the first day of the date's month.	Date and Time (Chrono)
LocalDate.ToIsoString	Returns the date as text in the form 2026-08-13, or empty text if it is Invalid.	Date and Time (Chrono)
LocalDate.ToString	Returns the date as ISO 8601 text, the same as ToIsoString.	Date and Time (Chrono)
LocalDate.TryParseIso	Reads ISO text into a date; returns false and sets it Invalid on failure.	Date and Time (Chrono)
LocalDate.Year	Returns the year, 1 to 9999.	Date and Time (Chrono)
LocalTime.CompareTo	Returns -1, 0 or 1 to order two times of day, or -2 if either is Invalid.	Date and Time (Chrono)
LocalTime.FromTicks	Creates a time of day from 100 ns ticks since midnight, or Invalid past a whole day.	Date and Time (Chrono)
LocalTime.Hour	Returns the hour, 0 to 23.	Date and Time (Chrono)
LocalTime.Invalid	Returns the Invalid time of day, which never equals anything, itself included.	Date and Time (Chrono)
LocalTime.IsValid	Returns true if the time of day is in range.	Date and Time (Chrono)
LocalTime.LocalTime	Creates a time of day from hours, minutes, seconds and milliseconds; midnight if none.	Date and Time (Chrono)
LocalTime.MaxValue	Returns the last tick of the day, 23:59:59.9999999.	Date and Time (Chrono)
LocalTime.Microsecond	Returns the microseconds within the second, the milliseconds included.	Date and Time (Chrono)
LocalTime.Midnight	Returns the time of day 00:00:00.	Date and Time (Chrono)
LocalTime.Millisecond	Returns the milliseconds within the second, 0 to 999.	Date and Time (Chrono)
LocalTime.Minute	Returns the minute, 0 to 59.	Date and Time (Chrono)
LocalTime.Noon	Returns the time of day 12:00:00.	Date and Time (Chrono)
LocalTime.ParseIso	Reads ISO text such as 14:30:05 into a time of day, or Invalid on failure.	Date and Time (Chrono)
LocalTime.Second	Returns the second, 0 to 59.	Date and Time (Chrono)
LocalTime.Ticks	Returns the time of day as 100 ns ticks since midnight.	Date and Time (Chrono)
LocalTime.ToIsoString	Returns the time of day as ISO 8601 text, such as 14:30:05.	Date and Time (Chrono)
LocalTime.ToString	Returns the time of day as ISO 8601 text, the same as ToIsoString.	Date and Time (Chrono)
LocalTime.TryParseIso	Reads ISO text into a time of day; returns false and sets it Invalid on failure.	Date and Time (Chrono)
Locate	Moves the text cursor to a row and column, and can show or hide it.	Console Functions
Lock	Restricts other programs' access to a record or byte range of an open file.	File I/O Functions
Lock	Returns a SharedPtr to the object if it still exists, or a null one if not.	Smart Pointers
LOF	Returns the length in bytes of an open file.	File I/O Functions
Log	Returns the natural logarithm; zero gives minus infinity and a negative gives NaN.	Mathematical Functions
Log	Logs a message at a level you pass, or returns a record to add fields to.	Logging
Log10	Returns the base-10 logarithm of a number.	Math Library
Log1p	Returns the natural logarithm of one plus a number, accurately near zero.	Math Library
Log2	Returns the base-2 logarithm of a number.	Math Library
LogB	Returns the binary exponent of a number as a floating-point value.	Math Library
LogEvent.AddBool	Adds a named true or false field.	Logging
LogEvent.AddError	Adds a filesystem error as fields: its message, its code and any system error code.	Logging
LogEvent.AddFloat	Adds a named floating-point field.	Logging
LogEvent.AddInt	Adds a named integer field, which stays a number in JSON output.	Logging
LogEvent.AddPtr	Adds a named pointer field, such as the address of an object.	Logging
LogEvent.AddSpan	Adds a named field holding a length of time, such as how long a step took.	Logging
LogEvent.AddText	Adds a named text field to the record and returns the record for the next call.	Logging
LogEvent.AddTime	Adds a named field holding a point in time.	Logging
LogEvent.AddUInt	Adds a named unsigned 64-bit integer field.	Logging
LogEvent.AddValue	Adds a named field from a value you built yourself, of any supported kind.	Logging
LogEvent.Msg	Sets the message and sends the record; a record that is never sent logs nothing.	Logging
LogEvent.Send	Sends the record without a message, for a record that is only fields.	Logging
LogEvent.Site	Records the file, line and procedure the record came from.	Logging
Logging		Logging
Logical Operators	Operators that perform bitwise logic.	Operators
Long	Standard data type: 32-bit signed integer.	Standard Data Types
LongInt	Standard data type: 64 bit signed.	Standard Data Types
Loop	Control flow statement for looping.	Miscellaneous Keywords
LoWord	Returns the lowest 16 bits of a number.	Bit Manipulation
LPos	Returns the number of characters sent to the printer port in the last LPrint statement.	Miscellaneous Keywords
LPrint	Writes text to the default printer.	Miscellaneous Keywords
LSet	Copies a string into another, left-justified and padded with spaces.	String Functions
LStat	Returns a path's FileInfo without following a symbolic link, so a link describes itself.	Filesystem
LTrim	Removes spaces, or the given characters, from the start.	String Functions

M

Name	What it does	Category
#Macro...#Endmacro	Preprocessor directive to define a multiline macro.	Preprocessor
MakeShared	Creates a default-constructed object and returns the first SharedPtr to it.	Smart Pointers
MakeSharedFrom	Creates a copy of a value on the heap and returns a SharedPtr to it.	Smart Pointers
Map		Map
Map	Holds key and value pairs in a hash table, so you find a value by its key.	Map
MapIterator	Holds a position in a Map; each step gives a pair read through .key and .value.	Map
MapPairIter	Holds a position in Map.Pairs; each step gives the key and value as a tuple.	Map
MapPairView	Holds the view that Map.Pairs returns, for for each (k, v) to walk.	Map
MatchPattern	Returns true if a string matches a wildcard pattern, without touching the disk.	Filesystem
Math Library		Math Library
Mathematical Functions	Procedures that work with numbers mathematically.	Mathematical Functions
Max	Returns the larger of two values; a NaN argument gives NaN.	Math Library
MaxOf	Returns the largest value in an array, or NaN if it is empty.	Math Library
MaxValue	Returns the largest value added so far.	Math Library
MCase	Returns a title-case copy: each word capitalised, the rest lower case.	String Library
Mean	Returns the average of an array, or NaN if it is empty.	Math Library
Median	Returns the middle value of an array, without reordering it.	Math Library
Memory Functions	Procedures that work with static and dynamic memory.	Memory Functions
Memory Operators	Operators that work with memory.	Operators
MemoryMappedFile.Close	Unmaps the file; harmless when nothing is mapped.	Filesystem
MemoryMappedFile.Data	Returns a pointer to the mapped bytes, valid until Close.	Filesystem
MemoryMappedFile.Flush	Writes changed mapped bytes to the disk now.	Filesystem
MemoryMappedFile.IsOpen	Returns true while a file is mapped.	Filesystem
MemoryMappedFile.Open	Maps a file into memory, read-only unless writable is true; an empty file fails.	Filesystem
MemoryMappedFile.Size	Returns the size of the mapped file in bytes.	Filesystem
Merge	Combines another accumulator's values into this one, exactly.	Math Library
Mid (Function)	Returns the characters from a position, optionally for a given length.	String Functions
Mid (Statement)	Overwrites part of a string in place with other text.	String Functions
Min	Returns the smaller of two values; a NaN argument gives NaN.	Math Library
MinLevel	Sets or returns the lowest level the logger emits; LOG_OFF silences it.	Logging
MinOf	Returns the smallest value in an array, or NaN if it is empty.	Math Library
MinSubnormalDouble	Returns the smallest Double above zero.	Math Library
MinSubnormalSingle	Returns the smallest Single above zero.	Math Library
Minute	Returns the minute of a date serial.	Date and Time Functions
MinValue	Returns the smallest value added so far.	Math Library
Miscellaneous Keywords		Miscellaneous Keywords
MKD	Copies a Double's bytes into an 8-byte string.	String Functions
MkDir	Creates one folder, whose parent must already exist; returns 0 on success.	Operating System Functions
MKI	Copies an integer's bytes into a string.	String Functions
MKL	Copies a Long's bytes into a 4-byte string.	String Functions
MKLongInt	Copies a LongInt's bytes into an 8-byte string.	String Functions
MKS	Copies a Single's bytes into a 4-byte string.	String Functions
MKShort	Copies a Short's bytes into a 2-byte string.	String Functions
Modf	Splits a number into whole and fractional parts that both keep its sign.	Math Library
Modularizing	Keywords helpful when writing modular programs.	Modularizing
MoneyCompose	Assembles a number, symbol and sign in one of the standard layouts.	String Library
MoneyFormat	Holds an amount and prints it the way the user's locale writes money.	String Library
MoneyLayoutFromICurrency	Converts a Windows positive-currency code into layout flags.	String Library
MoneyLayoutFromINegCurr	Converts a Windows negative-currency code into layout flags.	String Library
MoneyLocaleIsValid	Returns false if the system rejected the money locale.	String Library
MoneyLocaleName	Returns the name of the locale that money is formatted for.	String Library
MoneyRefreshLocale	Rereads the locale's money settings after the user changes them.	String Library
MoneySetLocale	Switches money formatting to a named locale; returns false if it is unknown.	String Library
Month	Returns the month of a date serial, 1 to 12.	Date and Time Functions
MonthName	Returns the name of a month number in the system's language, or its abbreviation.	Date and Time Functions
MoveFile	Moves or renames a file, even across volumes; refuses an existing destination by default.	Filesystem
MoveNext		For Each
Mul	Multiplies two vectors component by component.	Math Library
MulChecked	Multiplies two integers, returning an empty Optional if the result would overflow.	Math Library
MulSaturating	Multiplies two integers, clamping the result to the type's minimum or maximum.	Math Library
MultiKey	Returns -1 while the key with a given scancode is held down, or 0 if it is not.	User Input Functions (Graphics Library)
MulWrapping	Multiplies two integers and wraps around on overflow, on purpose.	Math Library
MutexCreate	Creates a mutex and returns its handle, or 0 on failure.	Threading Support Functions
MutexDestroy	Destroys a mutex once no thread is using it.	Threading Support Functions
MutexLock	Locks a mutex, waiting while another thread holds it.	Threading Support Functions
MutexUnlock	Unlocks a mutex so that a waiting thread can take it.	Threading Support Functions

N

Name	What it does	Category
NaiveSum	Adds up an array with a plain loop: faster than Sum, but small values can be lost.	Math Library
Naked	Write functions without prolog/epilog code.	Procedures
Name	Renames or moves a file or folder; returns 0 on success.	Operating System Functions
Name	Sets or returns the logger's component name, attached to every record it makes.	Logging
Namespace	Declares a namespace block.	Modularizing
NaN	Returns a Double that is NaN, not a number.	Math Library
NaNF	Returns a Single that is NaN, not a number.	Math Library
NegChecked	Negates an integer, returning an empty Optional for the most negative value.	Math Library
NegInfinity	Returns negative infinity as a Double.	Math Library
NegInfinityF	Returns negative infinity as a Single.	Math Library
NegSaturating	Negates an integer; the most negative value becomes the maximum instead.	Math Library
NegWrapping	Negates an integer within its type, so the most negative value stays as it is.	Math Library
Next	Control flow statement to mark the end of a For...Next loop.	Miscellaneous Keywords
NextAfter	Returns the next representable number after x in the direction of y.	Math Library
NextBoolean	Returns true or false with equal chance.	Math Library
NextBooleanP	Returns true with probability p, from 0 for never to 1 for always.	Math Library
NextDouble	Returns a random Double from 0 up to but not including 1, with 53 random bits.	Math Library
NextDoubleRange	Returns a random Double from lo up to but not including hi.	Math Library
NextExponential	Returns a random waiting time between events at rate lambda; its mean is 1/lambda.	Math Library
NextInt	Returns a random whole number from lo to hi, both included, without bias.	Math Library
NextNormal	Returns a random value from the normal distribution, mean 0 and standard deviation 1.	Math Library
NextNormalP	Returns a random value from a normal distribution with the given mean and deviation.	Math Library
NextPoisson	Returns a random count of events in one interval at rate lambda; its mean is lambda.	Math Library
NextPow2	Returns the smallest power of two at or above the value; zero gives 1.	Math Library
NextSingle	Returns a random Single from 0 up to but not including 1.	Math Library
NextULong	Returns a random 32-bit unsigned value.	Math Library
NextULongInt	Returns a random 64-bit unsigned value, the generator's raw output.	Math Library
None	Returns an empty Optional of the type you write out.	Optional
Normalize	Returns a vector of length 1 in the same direction; a zero vector stays zero.	Math Library
Now	Returns the current local date and time as a date serial.	Date and Time Functions
Nullptr		Nullptr

O

Name	What it does	Category
Object	Built-in type providing run-time type information.	Standard Data Types
Oct	Returns a number as octal text.	String Functions
OffsetOf	Returns the offset of a field within a type.	Miscellaneous Keywords
Ok	Returns a successful Result holding the value; both types must be written out.	Result
On Error	Sets a label to jump to when a runtime error happens; On Error Goto 0 turns it off.	Error Handling Functions
On...Gosub	Calls a label based on an expression.	Control Flow Statements
On...Goto	Jumps to a label based on an expression.	Control Flow Statements
Open	Opens a file on a file number for reading or writing text, bytes or records.	File I/O Functions
Open Com	Opens a serial port on a file number, with its speed, parity and other settings.	File I/O Functions
Open Cons	Opens standard input or output on a file number, to use like a file.	File I/O Functions
Open Err	Opens standard input and standard error on a file number, to use like a file.	File I/O Functions
Open Lpt	Opens a printer on a file number, so Print # and Put # send data to it.	File I/O Functions
Open Pipe	Runs a shell command and opens its input or output on a file number.	File I/O Functions
Open Scrn	Opens the screen on a file number, for reading and writing like a file.	File I/O Functions
Operating System Functions	Statements and procedures for working with files, directories and the system.	Operating System Functions
Operator	Declares or defines an overloaded operator.	User Defined Types
Operator ! (Escaped String Literal)	Explicitly indicates that a string literal should be processed for escape sequences.	Operators
Operator # (Preprocessor Stringize)	Preprocessor operator to convert macro arguments to strings.	Operators
Operator ## (Preprocessor Concatenate)	Preprocessor operator to concatenate strings.	Operators
Operator $ (Non-Escaped String Literal)	Explicitly indicates that a string literal should not be processed for escape sequences.	Operators
Operator & (String Concatenation With Conversion)	Concatenates two strings, converting non-strings to strings as needed.	Operators
Operator &= (Concatenate And Assign)	Appends and assigns a string onto another string.	Operators
Operator () (Array Index)	Returns a reference to an element in an array.	Operators
Operator * (Multiply)	Multiplies two numeric expressions.	Operators
Operator * (Value Of)	Dereferences a pointer.	Operators
Operator *= (Multiply And Assign)	Multiplies and assigns a value to a variable.	Operators
Operator + (Addition)	Sums two expressions.	Operators
Operator + (String Concatenation)	Concatenates two strings.	Operators
Operator += (Add And Assign)	Adds and assigns a value to a variable.	Operators
Operator - (Negate)	Changes the sign of a numeric expression.	Operators
Operator - (Subtract)	Subtracts two expressions.	Operators
Operator -= (Subtract And Assign)	Subtracts and assigns a value to a variable.	Operators
Operator -> (Pointer To Member Access)	Returns a reference to a member from a pointer to an object.	Operators
Operator . (Member Access)	Returns a reference to a member from a reference to an object.	Operators
Operator / (Divide)	Divides two numeric expressions.	Operators
Operator /= (Divide And Assign)	Divides and assigns a value to a variable.	Operators
Operator < (Less Than)	Compares an expression less than another expression.	Operators
Operator <= (Less Than Or Equal)	Compares an expression less than or equal to another expression.	Operators
Operator <> (Not Equal)	Compares two expressions for inequality.	Operators
Operator = (Equal)	Compares two expressions for equality.	Operators
Operator =[>] (Assign)	Assigns a value to a variable.	Operators
Operator > (Greater Than)	Compares an expression greater than another expression.	Operators
Operator >= (Greater Than Or Equal)	Compares an expression greater than or equal to another expression.	Operators
Operator @ (Address Of)	Returns the address of a string literal, variable, object or procedure.	Operators
Operator [] (Pointer Index)	Returns a reference to memory offset from an address.	Operators
Operator [] (String Index)	Returns a reference to the numeric value of a character in a string.	Operators
Operator \ (Integer Divide)	Divides two Integer expressions.	Operators
Operator = (Integer Divide And Assign)	Integer divides and assigns a value to a variable.	Operators
Operator ^ (Exponentiate)	Raises a numeric expression to some power.	Operators
Operator ^= (Exponentiate And Assign)	Exponentiates and assigns a value to a variable.	Operators
Operator And (Conjunction)	Returns the bitwise-and (conjunction) of two numeric values.	Operators
Operator And= (Conjunction And Assign)	Performs a bitwise-and (conjunction) and assigns the result to a variable.	Operators
Operator Andalso (Short Circuit Conjunction)	Returns the short circuit-and (conjunction) of two numeric values.	Operators
Operator Cast	Operator to convert a UDT (User Defined Type) variable into a specified data type.	Operators
Operator Delete Overload	Member operator to overload memory deallocation process part provided by Operator Delete Statement when applying to a UDT (User Defined Type).	Operators
Operator Delete Statement	Operator to destroy data and free memory allocated with the Operator New Expression.	Operators
Operator Eqv (Equivalence)	Returns the bitwise-and (equivalence) of two numeric values.	Operators
Operator Eqv= (Equivalence And Assign)	Performs a bitwise-eqv (equivalence) and assigns the result to a variable.	Operators
Operator For (Iteration)	Declares or defines operators used by a For...Next loop with user defined type variables.	Operators
Operator Imp (Implication)	Returns the bitwise-and (implication) of two numeric values.	Operators
Operator Imp= (Implication And Assign)	Performs a bitwise-imp (implication) and assigns the result to a variable.	Operators
Operator Is (Run-Time Type Information)	Check if an object is compatible to a type derived from its compile-time type (in the context of inheritance)	Operators
Operator Let (Assign)	Indicates the assignment operator when overloading Operator = (Assignment)	Operators
Operator Let() (Assignment)	Assigns fields of a user defined type to a list of variables.	Operators
Operator List	List of operators used in FreeBASIC.	Operators
Operator Mod (Modulus)	Finds the remainder from a division operation.	Operators
Operator Mod= (Modulus And Assign)	Divides a value and assigns the remainder to a variable.	Operators
Operator New Expression	Operator to dynamically allocate memory and construct data of a specified type.	Operators
Operator New Overload	Member operator to overload dynamic memory allocation process part provided by Operator New Expression when applying to a UDT (User Defined Type).	Operators
Operator Next (Iteration)	Determines if a For...Next loop should be terminated.	Operators
Operator Not (Complement)	Returns the bitwise-not (complement) of a numeric value.	Operators
Operator Or (Inclusive Disjunction)	Returns the bitwise-or (inclusive disjunction) of two numeric values.	Operators
Operator Or= (Inclusive Disjunction And Assign)	Performs a bitwise-or (inclusive disjunction) and assigns the result to a variable.	Operators
Operator Orelse (Short Circuit Inclusive Disjunction)	Returns the short circuit-or (Inclusive Disjunction) of two numeric values.	Operators
Operator Placement New	Operator to construct an object at a specified memory address.	Operators
Operator Precedence		Language Documentation
Operator Procptr (Procedure Pointer And Vtable Index)	Returns the address of any procedure, and the index in the vtable for a virtual/abstract member procedure.	Operators
Operator Shl (Shift Left)	Shifts the bits of a numeric expression to the left.	Operators
Operator Shl= (Shift Left And Assign)	Shifts left and assigns a value to a variable.	Operators
Operator Shr (Shift Right)	Shifts the bits of a numeric expression to the right.	Operators
Operator Shr= (Shift Right And Assign)	Shifts right and assigns a value to a variable.	Operators
Operator Step (Iteration)	Increments the iterator of a For...Next loop.	Operators
Operator Strptr (String Pointer)	Returns the address of a string's character data.	Operators
Operator Varptr (Variable Pointer)	Returns the address of a variable or object.	Operators
Operator Xor (Exclusive Disjunction)	Returns the bitwise-xor (exclusive disjunction) of two numeric values.	Operators
Operator Xor= (Exclusive Disjunction And Assign)	Performs a bitwise-xor (exclusive disjunction) and assigns the result to a variable.	Operators
Operators	Procedures that operate on one or more operands.	Operators
Option Dynamic	Specifies variable-length array declarations.	Array Functions
Option Static	Reverts to default array declaration behavior.	Array Functions
Option()	Specifies additional attributes and/or characteristics of symbols.	Miscellaneous Keywords
Optional		Optional
Optional	Holds one value or nothing at all; a new one is empty.	Result
Or (Graphics Put)	Combines source and destination pixels with a bitwise Or, as a Put method.	2D Drawing Functions
OrderedMap	Holds key and value pairs kept sorted by key.	OrderedMap
OrderedMap and OrderedSet		OrderedMap
OrderedMap.Add	Adds a key and value if the key is new; an existing value is left alone.	OrderedMap
OrderedMap.BlackHeight	Returns the tree's black height, or -1 if its balancing rules are broken.	OrderedMap
OrderedMap.Clear	Removes every entry.	OrderedMap
OrderedMap.Contains	Returns true if the key is present, without adding it.	OrderedMap
OrderedMap.Count	Returns the number of entries; reading an absent key with m[ k ] adds one.	OrderedMap
OrderedMap.GetIterator	Returns an iterator over the entries in ascending key order.	OrderedMap
OrderedMap.IsEmpty	Returns true if the map has no entries.	OrderedMap
OrderedMap.Keys	Returns a copy of all the keys as an Array, already sorted.	OrderedMap
OrderedMap.Pairs	Returns a view that lets for each (k, v) walk keys and values in key order.	OrderedMap
OrderedMap.Put	Stores a value under a key, replacing any old one; returns true if the key was new.	OrderedMap
OrderedMap.Remove	Removes a key and its value; returns true if the key was there.	OrderedMap
OrderedMap.TryCeiling	Finds the smallest key at or above a given one; returns false if there is none.	OrderedMap
OrderedMap.TryFirst	Copies the smallest key and its value into variables; returns false if the map is empty.	OrderedMap
OrderedMap.TryFloor	Finds the largest key at or below a given one; returns false if there is none.	OrderedMap
OrderedMap.TryGet	Copies the value for a key into a variable; returns false, adding nothing, if absent.	OrderedMap
OrderedMap.TryLast	Copies the largest key and its value into variables; returns false if the map is empty.	OrderedMap
OrderedMap.Values	Returns a copy of all the values as an Array, in the order of their keys.	OrderedMap
OrderedMapIterator	Holds a position in an OrderedMap, stepping in ascending key order.	OrderedMap
OrderedMapPairIter	Holds a position in OrderedMap.Pairs, giving key and value as a tuple in key order.	OrderedMap
OrderedMapPairView	Holds the view that OrderedMap.Pairs returns, for for each (k, v) to walk.	OrderedMap
OrderedSet	Holds each value at most once, kept in sorted order.	OrderedSet
OrderedSet.Add	Adds a value; returns false if it was already there.	OrderedSet
OrderedSet.BlackHeight	Returns the tree's black height, or -1 if its balancing rules are broken.	OrderedSet
OrderedSet.Clear	Removes every value.	OrderedSet
OrderedSet.Contains	Returns true if the value is in the set.	OrderedSet
OrderedSet.Count	Returns the number of values in the set.	OrderedSet
OrderedSet.ExceptWith	Removes every value that is also in another set.	OrderedSet
OrderedSet.GetIterator	Returns an iterator over the values in ascending order.	OrderedSet
OrderedSet.IntersectWith	Keeps only the values that are also in another set.	OrderedSet
OrderedSet.IsEmpty	Returns true if the set has no values.	OrderedSet
OrderedSet.Items	Returns a copy of all the values as an Array, already sorted.	OrderedSet
OrderedSet.Remove	Removes a value; returns true if it was there.	OrderedSet
OrderedSet.TryCeiling	Finds the smallest value at or above a given one; returns false if there is none.	OrderedSet
OrderedSet.TryFirst	Copies the smallest value into a variable; returns false if the set is empty.	OrderedSet
OrderedSet.TryFloor	Finds the largest value at or below a given one; returns false if there is none.	OrderedSet
OrderedSet.TryLast	Copies the largest value into a variable; returns false if the set is empty.	OrderedSet
OrderedSet.UnionWith	Adds every value of another set to this one; the other set is unchanged.	OrderedSet
OrderedSetIterator	Holds a position in an OrderedSet, stepping in ascending order.	OrderedSet
Out	Outputs a value to a hardware port.	Miscellaneous Keywords
Output	Opens a text file for writing with Open, creating it or emptying it first.	File I/O Functions
Overload	Specifies that a procedure name can be overloaded.	Procedures
Override	Method attribute; specifies that a method must override a virtual.	User Defined Types

P

Name	What it does	Category
#pragma	Preprocessor directive.	Preprocessor
#Pragma Reserve	Preprocessor directive.	Preprocessor
#print	Preprocessor diagnostic directive.	Preprocessor
[(Print	?) #](procedures-Print)	Writes values as text to an open file; a trailing comma or semicolon skips the line break.
[(Print	?) Using](Print-Using)	Writes values formatted by a template such as "##.##" or "&".
PadCenter	Centres the string in a width, padding both sides.	String Library
PadLeft	Pads on the left to a width, with spaces or a given character.	String Library
PadRight	Pads on the right to a width, with spaces or a given character.	String Library
Paint	Fills the area enclosed by a border colour with a colour or a pattern.	2D Drawing Functions
Pairs	Returns a view that lets for each (k, v) give each key and value as two variables.	Map
Palette	Sets or reads the colours of a palette mode, or restores the default palette.	2D Drawing Functions
Parity	Returns 1 if an odd number of bits are set, or 0 if an even number are.	Math Library
Partial	Writes one type or class in several blocks of one compilation unit.	Partial Types
pascal	Specifies a Pascal-style calling convention in a procedure declaration.	Procedures
PathChangeExtension	Replaces a path's extension, or removes it when the new one is empty.	Filesystem
PathEquals	Returns true if two paths match once normalised; case-insensitive on Windows.	Filesystem
PathExtension	Returns the extension with its dot, such as .tiko, or an empty string if there is none.	Filesystem
PathFileName	Returns the last part of a path, the file name, or an empty string for a root.	Filesystem
PathHasExtension	Returns true if the file name has an extension; a dotfile has none.	Filesystem
PathIsAbsolute	Returns true if a path needs no current folder; C:dev and \dev are not absolute.	Filesystem
PathIsCaseSensitive	Returns true if paths compare case-sensitively here: on Linux and macOS, not Windows.	Filesystem
PathIsRoot	Returns true if the whole path is just a root, such as C:\ or /.	Filesystem
PathJoin	Joins two to four path parts with one separator; an absolute part drops those before it.	Filesystem
PathNextComponent	Finds the next part of a path from an offset; returns a negative number when none is left.	Filesystem
PathNormalize	Returns a tidied path: . removed, .. resolved as text, duplicate separators collapsed.	Filesystem
PathParent	Returns the path without its last part, or an empty string for a root.	Filesystem
PathRelativeTo	Returns a path relative to a base folder; fails if the two have different roots.	Filesystem
PathRoot	Returns the root of a path, such as C:\ or /, or an empty string for a relative path.	Filesystem
PathRootLen	Returns the length of a path's root, in characters.	Filesystem
PathSeparator	Returns the platform's path separator: a backslash on Windows, a slash on Linux and macOS.	Filesystem
PathSplit	Splits a normalised path into its parts, without the root, in an Array; returns the count.	Filesystem
PathStartsWith	Returns true if a path begins with another, comparing whole parts, not characters.	Filesystem
PathStem	Returns the file name without its extension; a dotfile such as .gitignore keeps its name.	Filesystem
PathToNative	Returns the path with the platform's separators, duplicates collapsed, nothing resolved.	Filesystem
PatternIsRecursive	Returns true if a pattern has a double-star part that searches every subfolder.	Filesystem
PatternWildcardAt	Returns the offset of a pattern's first wildcard, or -1 if it has none.	Filesystem
PCopy	Copies one graphics or text page onto another.	Screen Functions
Peek	Returns a reference to the value at an address, as a byte or as a given type.	Memory Functions
Percentile	Returns the value below which p percent of an array falls, with p from 0 to 100.	Math Library
PMap	Converts a coordinate between the Window system and physical pixels.	Screen Functions
Point	Returns the colour of a pixel, or -1 if it is off the screen or image.	2D Drawing Functions
PointCoord	Returns the x or y position of the Draw pen.	Screen Functions
Pointer Operators	Operators that work with pointers.	Operators
[Pointer	Ptr](Pointer-Ptr)	A variable declaration type modifier.
Poke	Writes a value to an address, as a byte or as a given type.	Memory Functions
Pop	Removes and returns the last element, or a default value if the array is empty.	Array
PopBack	Removes and returns the back value, or a default value if the list is empty.	LinkedList
PopCount	Counts the bits that are set.	Math Library
PopFront	Removes and returns the front value, or a default value if the list is empty.	LinkedList
Pos	Returns the column the cursor is in, counting from 1 at the left.	Console Functions
Pow	Returns one floating-point number raised to the power of another.	Math Library
Preprocessor	Commands that control the preprocessor.	Preprocessor
Preprocessor Operators	Operators that are executed by the preprocessor.	Operators
Preserve	Keeps the existing elements when ReDim resizes an array.	Array Functions
PReset	Plots one pixel, in the given colour or the current background colour.	2D Drawing Functions
[Print	?](Print)	Writes values to the console, then a new line unless it ends with a comma or semicolon.
Private	Specifies a procedure having internal linkage.	Modularizing
Private: (Access Control)	Specifies private member access control in a Type or Class.	User Defined Types
Procedures	Keywords that work with procedures.	Procedures
Programmer's Guide	FreeBASIC programmer's guide.	Programmer's Guide
Property	Declares or defines a property in a type or class.	User Defined Types
Protected: (Access Control)	Specifies protected member access control in a Type or Class.	User Defined Types
Pset (Graphics Put)	Copies source pixels over the destination unchanged, as a Put method.	2D Drawing Functions
Pset (Statement)	Plots one pixel, in the given colour or the current foreground colour.	2D Drawing Functions
Public	Specifies a procedure having external linkage.	Modularizing
Public: (Access Control)	Specifies public member access control in a Type or Class.	User Defined Types
Push	Adds a value at the end, growing the array as needed.	Array
PushBack	Adds a value at the back of the list.	LinkedList
PushFront	Adds a value at the front of the list.	LinkedList
Put	Stores a value under a key, replacing any old one; returns true if the key was new.	Map
Put (File I/O)	Writes a variable, string or array to a file as bytes, at a position or the current one.	File I/O Functions
Put (Graphics)	Draws an image onto the screen or another image, with a choice of blending method.	2D Drawing Functions

R

Name	What it does	Category
RadToDeg	Converts an angle from radians to degrees.	Math Library
RaiseFpException	Raises a floating-point exception flag by hand; returns true on success.	Math Library
Random	Opens a file with Open for reading and writing fixed-size records, 128 bytes by default.	File I/O Functions
Randomize	Seeds the random number generator that Rnd uses, and can choose its algorithm.	Mathematical Functions
Range	Returns the largest value in an array minus the smallest.	Math Library
Raw	Returns the stored integer, the amount times 10000, for saving to a file or database.	Finance
Read	Reads values stored with the Data statement.	Miscellaneous Keywords
Read (File Access)	Opens a Binary or Random file for reading only, in an Access clause.	File I/O Functions
Read Write (File Access)	Opens a Binary or Random file for both reading and writing, the default.	File I/O Functions
ReadAllBytes	Reads a whole file into an Array of bytes; returns the number read.	Filesystem
ReadAllLines	Reads a file's lines into an Array, without their line endings; returns the count.	Filesystem
ReadAllText	Reads a whole file as UTF-8 text into a string, or fails if it cannot be read.	Filesystem
ReadDir	Lists the entries of one folder for a for each loop; each entry may be a failure to check.	Filesystem
ReadLink	Returns the target a symbolic link points to, as stored; fails if it is not a link.	Filesystem
Reallocate	Resizes a block, keeping its contents, and returns the new pointer, or 0 on failure.	Memory Functions
ReDim	Creates or resizes a variable-length array; elements are reset unless Preserve is used.	Array Functions
Ref	Returns a reference to the object; raises an error if the handle is null.	Smart Pointers
Reflect	Reflects a vector off a surface, given the surface's normalised normal.	Math Library
Relational Operators	Operators that compare relationships.	Operators
Rem	Indicates comments in the source code.	Miscellaneous Keywords
Remain	Returns the text after a match, or an empty string if there is none.	String Library
RemainChars	Returns the text after the first character from a set.	String Library
Remove	Removes every occurrence of the text.	String Library
Remove	Removes the element at a position, keeping the rest in order.	Array
Remove	Removes a key and its value; returns true if the key was there.	Map
Remove	Removes a value; returns true if it was there.	Set
RemoveBetween	Removes a pair of delimiters and the text between them.	String Library
RemoveChars	Removes every character that belongs to a set.	String Library
RemoveDir	Deletes an empty folder; fails if it still holds anything.	Filesystem
RemoveDirAll	Deletes a folder and all it holds without following links; returns how many it removed.	Filesystem
RemoveFile	Deletes a file; fails if it is not there.	Filesystem
RemoveSink	Detaches one sink; removing one that was never added does nothing.	Logging
RemoveSwap	Removes the element at a position quickly by moving the last element into its place.	Array
Repeat	Returns a string repeated n times.	String Library
Replace	Replaces every occurrence of the text with other text.	String Library
ReplaceChars	Replaces each character from a set with one given character.	String Library
ReplaceFile	Replaces one file with another in a single step, so the target is never missing.	Filesystem
Reserve	Makes room for at least n elements without adding any; it never shrinks.	Array
Reserve	Makes room for n entries, so filling the map does not have to regrow it.	Map
Reserve	Makes room for n values, so filling the set does not have to regrow it.	Set
Reset	Closes every open file, or resets a redirected standard input or output stream.	File I/O Functions
Reset	Drops this handle's share and leaves it null; the last one out destroys the object.	Smart Pointers
Reset	Empties the accumulator so that it can be reused.	Math Library
Restore	Changes the next read location for values stored with the Data statement.	Miscellaneous Keywords
Result		Result
Result	Holds either a value or the reason it could not be made; a new one counts as failed.	Result
RetainChars	Keeps only the characters that belong to a set.	String Library
Return (From Gosub)	Control flow statement to return from a procedure or GoSub.	Control Flow Statements
Return (From Procedure)	Control flow statement to return from a procedure or GoSub.	Control Flow Statements
Reverse	Returns the string with its characters in reverse order.	String Library
RGB	Returns an opaque colour value from red, green and blue parts of 0 to 255.	2D Drawing Functions
RGBA	Returns a colour value from red, green, blue and alpha parts of 0 to 255.	2D Drawing Functions
Right	Returns the last n characters.	String Functions
RmDir	Removes an empty folder; returns 0 on success or -1 on failure.	Operating System Functions
Rnd	Returns a random Double from 0 up to but not including 1.	Mathematical Functions
RngFromEntropy	Creates a random generator seeded by the operating system, different on every run.	Math Library
RngSeeded	Creates a random generator from a seed, so the same seed repeats the same sequence.	Math Library
Rotate	Rotates a vector by a normalised quaternion.	Math Library
Round	Rounds to the nearest whole number or number of decimals, halves away from zero.	Math Library
RoundHalfEven	Rounds to the nearest whole number or number of decimals, halves to the even side.	Math Library
RoundMode	Returns the amount rounded to 0 to 4 places by a rounding rule you name.	Finance
RSet	Copies a string into another, right-justified and padded with spaces.	String Functions
RTrim	Removes spaces, or the given characters, from the end.	String Functions
Run	Hands control to another program and ends this one; returns -1 if it cannot start.	Operating System Functions

S

Name	What it does	Category
$Static	Metacommand to change the way arrays are allocated.	Array Functions
SAdd	Returns a pointer to the characters of a string.	Memory Functions
ScaleB	Multiplies a number by a power of two exactly, by adjusting its exponent.	Math Library
Scope...End Scope	Statement to begin a new scope block.	Variable Declarations
Screen (Console)	Returns the character, or its colour, at a row and column of the console.	Console Functions
Screen (Graphics)	Opens a graphics mode by mode number, or picks the work and visible pages.	Screen Functions
Screen Functions	Statements and procedures that work with the graphics display.	Screen Functions
ScreenControl	Sets or reads graphics library settings, such as the driver or the window position.	Screen Functions
ScreenCopy	Copies one graphics page onto another, by default the work page onto the shown one.	Screen Functions
ScreenEvent	Returns -1 if a mouse, keyboard or window event is waiting, and fetches it.	Screen Functions
ScreenGLProc	Returns the address of an OpenGL procedure by name, or 0 if it is not found.	Screen Functions
ScreenInfo	Fills in the screen's width, height, depth and driver, or the desktop's if none is open.	Screen Functions
ScreenList	Returns the fullscreen resolutions for a colour depth, one per call, then 0.	Screen Functions
ScreenLock	Stops screen updates while you draw, so the user never sees half a frame.	Screen Functions
ScreenPtr	Returns a pointer to the work page's pixels, or 0 if no graphics mode is set.	Screen Functions
ScreenRes	Opens a graphics window of a given width, height and colour depth.	Screen Functions
ScreenSet	Sets which page is drawn on and which page is shown.	Screen Functions
ScreenSync	Waits for the display to finish drawing a frame, to reduce flicker.	Screen Functions
ScreenUnlock	Resumes screen updates after ScreenLock and shows what was drawn.	Screen Functions
Second	Returns the second of a date serial.	Date and Time Functions
Seek (Function)	Returns the 1-based position of the next read or write: bytes, or records for Random.	File I/O Functions
Seek (Statement)	Sets the 1-based position of the next read or write: bytes, or records for Random.	File I/O Functions
Select Case	Conditional statement block.	Control Flow Statements
Set		Set
Set	Holds each value at most once, in no particular order.	Set
SetCurrentDir	Changes the program's current folder, for every thread at once.	Filesystem
SetDate	Sets the system date from text like mm-dd-yyyy; needs admin rights, 0 means success.	Date and Time Functions
SetEnviron	Sets an environment variable from "NAME=value" text; returns 0 on success.	Operating System Functions
SetHidden	Sets or clears a file's hidden flag on Windows; fails as unsupported on Linux and macOS.	Filesystem
SetIterator	Holds a position in a Set; changing a value through it loses that value.	Set
SetMouse	Moves the mouse pointer, shows or hides it, or keeps it inside the window.	User Input Functions (Graphics Library)
SetPosixMode	Sets a file's permission bits on Linux and macOS; fails as unsupported on Windows.	Filesystem
SetReadOnly	Sets or clears a file's read-only flag, or its write bits on Linux and macOS.	Filesystem
SetRoundingMode	Sets the direction floating-point results are rounded in; returns true on success.	Math Library
SetTime	Sets the system time from text like hh:mm:ss; needs admin rights, 0 means success.	Date and Time Functions
SetTimes	Sets a file's modified and accessed times; a time of 0 leaves that one alone.	Filesystem
SetWin32Attributes	Replaces a file's whole Windows attribute word; fails as unsupported on Linux and macOS.	Filesystem
Sgn	Returns -1, 0 or 1 for the sign of a number, in the number's own type.	Mathematical Functions
Shared	Variable declaration modifier specifying visibility throughout a module.	Variable Declarations
Shared Libraries - DOS	A shared library is compiled code that can be loaded and used later when running an executable.	Programmer's Guide
SharedPtr	Holds an object shared by several owners and destroys it when the last one lets go.	Smart Pointers
SharedPtr and WeakPtr		Smart Pointers
Shell	Runs a command through the system shell, waits, and returns its exit code or -1.	Operating System Functions
Short	Standard data type: 16 bit signed.	Standard Data Types
Short Circuit Operators	Operators that perform a short circuit logical evaluation.	Operators
Shrink	Trims both ends and collapses each inner run of spaces to one.	String Library
Shrink	Releases unused room, cutting the capacity down to the count.	Array
Shuffle	Shuffles an array in place so that every order is equally likely.	Math Library
Sign	Returns -1, 0 or 1 for the sign of a number, always as a Long.	Math Library
Sin	Returns the sine of an angle in radians.	Mathematical Functions
Single	Standard data type: 32 bit floating point.	Standard Data Types
Sinh	Returns the hyperbolic sine of a number.	Math Library
Sink.Close	Closes a sink and releases what it holds; every kind of sink closes the same way.	Logging
Sink.DroppedCount	Returns how many records a sink could not write; the count never resets.	Logging
Sink.Flush	Flushes one sink on its own.	Logging
Sink.Write	Writes one record to a sink; the method a sink of your own overrides.	Logging
SinkCount	Returns how many sinks are attached to the logger.	Logging
SizeOf	Returns the size of a variable or type in bytes.	Miscellaneous Keywords
Sleep	Waits until a specified time has elapsed, or a key is pressed.	Miscellaneous Keywords
Slerp	Blends between two rotations at constant speed, taking the shorter way round.	Math Library
Some	Returns an Optional holding the value, its type taken from the argument.	Optional
Sort	Sorts an Array in ascending order in place; equal elements may change places.	Array
Sort	Sorts an Array in ascending order in place; equal elements may change places.	Sorting
SortBy	Sorts an Array in place by your comparer; equal elements may change places.	Array
SortBy	Sorts an Array in place by your comparer; equal elements may change places.	Sorting
Sorting		Sorting
SortList	Sorts a LinkedList in ascending order by relinking nodes; equal elements keep order.	LinkedList
SortList	Sorts a LinkedList in ascending order by relinking nodes; equal elements keep order.	Sorting
SortListBy	Sorts a LinkedList by your comparer, relinking nodes; equal elements keep order.	LinkedList
SortListBy	Sorts a LinkedList by your comparer, relinking nodes; equal elements keep order.	Sorting
Space	Returns a string of n spaces.	String Functions
SpanOf	Counts the run of characters from a set that starts at a position.	String Library
spawn	Runs a procedure alongside the program, copying its arguments at that moment.	Goroutines and Channels
Spc	Skips a number of columns inside a Print, leaving those cells unchanged.	Console Functions
SpCast	Returns a SharedPtr to a base type that shares ownership with the derived one.	Smart Pointers
Split	Breaks a string into an Array at each delimiter.	String Library
SplitChars	Breaks a string into an Array wherever a character from a set appears.	String Library
SplitCsv	Parses CSV text into rows and fields, quoted fields included.	String Library
SplitCsvRow	Parses one CSV record into an Array of fields.	String Library
SplitSlices	Walks the parts of a slice between separators, one at a time, in a for each loop.	String Slices
Sqr	Returns the square root of a number.	Mathematical Functions
StableSort	Sorts an Array in ascending order, keeping equal elements in their original order.	Array
StableSort	Sorts an Array in ascending order, keeping equal elements in their original order.	Sorting
StableSortBy	Sorts an Array by your comparer, keeping equal elements in their original order.	Array
StableSortBy	Sorts an Array by your comparer, keeping equal elements in their original order.	Sorting
Standard Data Type Limits	Standard variable types and limits.	Language Documentation
Standard Data Types	Built-in data types.	Standard Data Types
StartsWith	Returns true if the string begins with the given text.	String Library
Stat	Returns a path's FileInfo, following symbolic links; fails if the path is missing.	Filesystem
Static	Defines variables, objects and arrays having static storage.	Variable Declarations
Static (Member)	Declare a static member procedure or variable.	User Defined Types
stdcall	Specifies a stdcall-style calling convention in a procedure declaration.	Procedures
StdDev	Returns the sample standard deviation of an array, dividing by n-1.	Math Library
StdDevPopulation	Returns the population standard deviation of an array, dividing by n.	Math Library
Step	Statement modifier.	Miscellaneous Keywords
Stick	Reads axis position from attached gaming devices.	User Input Functions (Graphics Library)
Stop	Halts program execution, and waits for a key press before ending the program.	Miscellaneous Keywords
Stopwatch.Elapsed	Returns the time measured so far as a TimeSpan.	Date and Time (Chrono)
Stopwatch.ElapsedMilliseconds	Returns the time measured so far in whole milliseconds.	Date and Time (Chrono)
Stopwatch.ElapsedTicks	Returns the time measured so far in 100 ns ticks.	Date and Time (Chrono)
Stopwatch.Frequency	Returns how many counts per second the raw counter from GetTimestamp makes.	Date and Time (Chrono)
Stopwatch.GetTimestamp	Returns the raw monotonic counter; divide a difference by Frequency to get seconds.	Date and Time (Chrono)
Stopwatch.IsHighResolution	Returns true if the platform counter is finer than the system tick.	Date and Time (Chrono)
Stopwatch.IsRunning	Returns true while the stopwatch is running.	Date and Time (Chrono)
Stopwatch.Reset	Stops the stopwatch and sets its elapsed time back to zero.	Date and Time (Chrono)
Stopwatch.Restart	Sets the elapsed time back to zero and keeps the stopwatch running.	Date and Time (Chrono)
Stopwatch.Start	Starts the stopwatch, or resumes it and keeps the time already measured.	Date and Time (Chrono)
Stopwatch.StartNew	Creates a stopwatch that is already running.	Date and Time (Chrono)
Stopwatch.Stop_	Stops the stopwatch, freezing the elapsed time until it starts again.	Date and Time (Chrono)
Stopwatch.Stopwatch	Creates a stopped stopwatch on the monotonic clock, which never jumps.	Date and Time (Chrono)
Str	Returns a number or boolean as text.	Converting Data Types
Strig	Reads button state from attached gaming devices.	User Input Functions (Graphics Library)
String	Standard data type: 8 bit character string.	Operators
String (Function)	Returns a string of n copies of one character.	String Functions
String Functions	Statements and Procedures that work with strings.	String Functions
String Library		String Library
String Operators	Operators that work with strings.	Operators
Sub	Defines a procedure.	Procedures
Sub (Member)	Declares or defines a member procedure.	User Defined Types
Sub Pointer	Data type that stores a pointer to a Sub procedure.	Standard Data Types
SubChecked	Subtracts two integers, returning an empty Optional if the result would overflow.	Math Library
SubSaturating	Subtracts two integers, clamping the result to the type's minimum or maximum.	Math Library
SubWrapping	Subtracts two integers and wraps around on overflow, on purpose.	Math Library
Sum	Adds up an array with compensated summation, so small values are not lost.	Math Library
Swap	Exchanges the values of two variables.	Memory Functions
System	Closes all open files and ends the program, with an optional exit code.	Operating System Functions

T

Name	What it does	Category
Tab	Moves to a column inside a Print, on the next line if already past it.	Console Functions
Tally	Counts how many times the text occurs, without overlaps.	String Library
TallyChars	Counts the characters that belong to a set.	String Library
Tan	Returns the tangent of an angle in radians.	Mathematical Functions
Tanh	Returns the hyperbolic tangent of a number, which lies between -1 and 1.	Math Library
TempDir	Returns the system's temporary folder; creates nothing.	Filesystem
TestFpException	Returns true if a floating-point exception flag has been raised since it was cleared.	Math Library
TextRenderer.Render	Appends a record as one line of text to a buffer, without clearing it first.	Logging
Then	Control flow statement for conditional branching.	Miscellaneous Keywords
This	Hidden instance parameter passed to non-static member functions in a Type or Class.	User Defined Types
ThreadCall		Threading Support Functions
ThreadCreate	Starts a procedure on a new thread, passing it one pointer; returns the thread handle.	Threading Support Functions
ThreadDetach	Releases a thread handle without waiting; the thread runs on to its end.	Threading Support Functions
Threading Support Functions	Procedures for working with multithreaded applications.	Threading Support Functions
ThreadSelf	Returns the handle of the thread that calls it.	Threading Support Functions
ThreadWait	Waits for a thread to finish, then releases its handle.	Threading Support Functions
Time	Returns the current time as text in the form hh:mm:ss.	Date and Time Functions
Timer	Returns the seconds since a fixed starting point, for measuring elapsed time.	Date and Time Functions
TimeSerial	Returns the fraction of a day for an hour, minute and second, to add to a date serial.	Date and Time Functions
TimeSpan.Add	Returns the sum of two durations, or Invalid on overflow.	Date and Time (Chrono)
TimeSpan.CompareTo	Returns -1, 0 or 1 to order two durations, or -2 if either is Invalid.	Date and Time (Chrono)
TimeSpan.Days	Returns the days part of the duration, negative for a negative span.	Date and Time (Chrono)
TimeSpan.Divide	Returns the duration divided by a number, or Invalid when dividing by zero.	Date and Time (Chrono)
TimeSpan.DivideBy	Returns how many times one duration fits in another, as a double.	Date and Time (Chrono)
TimeSpan.Duration	Returns the absolute value of the duration.	Date and Time (Chrono)
TimeSpan.FromDays	Returns a duration of a number of days, fractions allowed.	Date and Time (Chrono)
TimeSpan.FromHours	Returns a duration of a number of hours, fractions allowed.	Date and Time (Chrono)
TimeSpan.FromMicroseconds	Returns a duration of a whole number of microseconds.	Date and Time (Chrono)
TimeSpan.FromMilliseconds	Returns a duration of a number of milliseconds, fractions allowed.	Date and Time (Chrono)
TimeSpan.FromMinutes	Returns a duration of a number of minutes, fractions allowed.	Date and Time (Chrono)
TimeSpan.FromSeconds	Returns a duration of a number of seconds, fractions allowed.	Date and Time (Chrono)
TimeSpan.FromTicks	Returns a duration of an exact number of 100 ns ticks.	Date and Time (Chrono)
TimeSpan.Hours	Returns the hours part, 0 to 23, negative for a negative span.	Date and Time (Chrono)
TimeSpan.Invalid	Returns the Invalid duration, which spreads to anything computed from it.	Date and Time (Chrono)
TimeSpan.IsNegative	Returns true if the duration is below zero.	Date and Time (Chrono)
TimeSpan.IsValid	Returns true unless the duration overflowed or came from bad input.	Date and Time (Chrono)
TimeSpan.IsZero	Returns true if the duration is exactly zero, and false if it is Invalid.	Date and Time (Chrono)
TimeSpan.MaxValue	Returns the longest duration a TimeSpan can hold.	Date and Time (Chrono)
TimeSpan.Microseconds	Returns the microseconds within the second, the milliseconds included.	Date and Time (Chrono)
TimeSpan.Milliseconds	Returns the milliseconds part, 0 to 999, negative for a negative span.	Date and Time (Chrono)
TimeSpan.Minutes	Returns the minutes part, 0 to 59, negative for a negative span.	Date and Time (Chrono)
TimeSpan.MinValue	Returns the most negative duration a TimeSpan can hold.	Date and Time (Chrono)
TimeSpan.Multiply	Returns the duration scaled by a factor, fractions allowed.	Date and Time (Chrono)
TimeSpan.Negate	Returns the duration with its sign flipped.	Date and Time (Chrono)
TimeSpan.ParseIso	Reads an ISO 8601 duration such as P1DT2H into a TimeSpan, or Invalid on failure.	Date and Time (Chrono)
TimeSpan.Seconds	Returns the seconds part, 0 to 59, negative for a negative span.	Date and Time (Chrono)
TimeSpan.Subtract	Returns the difference of two durations, which may be negative.	Date and Time (Chrono)
TimeSpan.Ticks	Returns the duration as a count of 100 ns ticks.	Date and Time (Chrono)
TimeSpan.TimeSpan	Creates a duration from ticks, or from hours, minutes and seconds, with or without days.	Date and Time (Chrono)
TimeSpan.ToIsoString	Returns the duration as ISO 8601 text, such as PT1H30M.	Date and Time (Chrono)
TimeSpan.ToString	Returns the duration as ISO 8601 text, the same as ToIsoString.	Date and Time (Chrono)
TimeSpan.TotalDays	Returns the whole duration in days, with a fraction.	Date and Time (Chrono)
TimeSpan.TotalHours	Returns the whole duration in hours, with a fraction.	Date and Time (Chrono)
TimeSpan.TotalMicroseconds	Returns the whole duration in whole microseconds.	Date and Time (Chrono)
TimeSpan.TotalMilliseconds	Returns the whole duration in milliseconds, with a fraction.	Date and Time (Chrono)
TimeSpan.TotalMinutes	Returns the whole duration in minutes, with a fraction.	Date and Time (Chrono)
TimeSpan.TotalSeconds	Returns the whole duration in seconds, with a fraction.	Date and Time (Chrono)
TimeSpan.TryParseIso	Reads an ISO 8601 duration; returns false and sets it Invalid on failure.	Date and Time (Chrono)
TimeSpan.Zero	Returns a duration of zero, the same as a new TimeSpan.	Date and Time (Chrono)
TimeValue	Returns the date serial of a time written like 23:59:59 or 11:59:59PM.	Date and Time Functions
TimeZoneInfo.DaylightName	Returns the OS's name for the local zone's daylight saving time.	Date and Time (Chrono)
TimeZoneInfo.IsDaylightSavingTime	Returns true if daylight saving time is in force in the local zone at a given moment.	Date and Time (Chrono)
TimeZoneInfo.LocalOffset	Returns the local zone's UTC offset in minutes right now.	Date and Time (Chrono)
TimeZoneInfo.LocalOffsetAt	Returns the local zone's UTC offset in minutes at a given moment, DST included.	Date and Time (Chrono)
TimeZoneInfo.StandardName	Returns the OS's name for the local zone's standard time.	Date and Time (Chrono)
TimeZoneInfo.SupportsDaylightSavingTime	Returns true if the local zone observes daylight saving time at all.	Date and Time (Chrono)
To	Statement modifier to specify a range.	Miscellaneous Keywords
ToDouble	Returns the amount as a double, which loses precision above about 900 billion.	Finance
ToMatrix	Converts a quaternion into the matching rotation matrix.	Math Library
ToString	Returns a number as the shortest text that reads back as exactly the same value.	Math Library
Total	Returns the running total as a Currency, rounded once; reading it does not reset it.	Finance
Trace	Logs a message at trace, the finest level, or returns a record to add fields to.	Logging
TrailingZeros	Counts the zero bits below the lowest set bit; zero gives the type's full width.	Math Library
Trans	Copies pixels with Put but skips the mask colour, magenta or index 0.	2D Drawing Functions
TransformPoint	Applies a matrix to a point, translation included.	Math Library
TransformVector	Applies a matrix to a direction, leaving out the translation.	Math Library
Transpose	Returns a matrix with its rows and columns swapped.	Math Library
Trim	Removes spaces, or the given characters, from both ends.	String Functions
TrimEnd	Returns a slice of the text without its trailing spaces, tabs, CRs and LFs.	String Slices
TrimSpace	Returns a slice of the text without the spaces, tabs, CRs and LFs at either end.	String Slices
TrimStart	Returns a slice of the text without its leading spaces, tabs, CRs and LFs.	String Slices
True	Intrinsic constant set by the compiler.	Intrinsic Defines
Truncate	Drops the fraction, rounding towards zero, so Truncate(-2.7) is -2.	Math Library
TryCast	Converts to an interface or a typed pointer if the object really is one, and answers null if it is not.	Interfaces
TryGet	Copies the value for a key into a variable; returns false, adding nothing, if absent.	Map
TryInverse	Writes the inverse of a matrix into a second one, or returns false if there is none.	Math Library
TryParseDouble	Parses a whole string as a Double, returning an empty Optional if it is not one.	Math Library
TryParseLong	Parses a whole string as a Long, returning an empty Optional if invalid or too big.	Math Library
TryParseLongInt	Parses a whole string as a LongInt, in an optional base; empty if invalid or too big.	Math Library
TryParseSingle	Parses a whole string as a Single, returning an empty Optional if it is not one.	Math Library
TryParseULong	Parses a whole string as a ULong, returning an empty Optional if invalid or too big.	Math Library
TryParseULongInt	Parses a whole string as a ULongInt, returning an empty Optional if invalid or too big.	Math Library
Tuples		Tuples
Type (Alias)	Declares an alternative name for a type.	User Defined Types
Type (Temporary)	Creates a temporary copy of a user defined type.	Programmer's Guide
Type (Udt)	Declares a user-defined type.	Operators
Type or Class Operators	Operators that work with objects.	Operators
TypeOf	Returns the type of a variable.	Miscellaneous Keywords

U

Name	What it does	Category
#undef	Preprocessor directive to undefine a macro.	Preprocessor
UBound	Returns the highest valid index of an array dimension, or -1 if there is none.	Array Functions
UByte	Standard data type: 8 bit unsigned. Equivalent to Unsigned Byte.	Standard Data Types
UCase	Returns an upper-case copy of the string.	String Functions
UInt16		Fixed-Width Types
UInt32		Fixed-Width Types
UInt64		Fixed-Width Types
UInt8		Fixed-Width Types
UInteger	Standard data type: 32-bit or 64-bit unsigned, same size as SizeOf(Any Ptr). Equivalent to Unsigned Integer.	Bit Manipulation
ULong	Standard data type: 32-bit unsigned integer. Equivalent to Unsigned Long.	Standard Data Types
ULongInt	Standard data type: 64 bit unsigned. Equivalent to Unsigned LongInt.	Standard Data Types
Ulp	Returns the gap between a number and the next one its type can hold.	Math Library
Unescape	Turns backslash escapes back into the characters they stand for.	String Library
Union	Declares a union user defined type.	User Defined Types
UnionWith	Adds every value of another set to this one; the other set is unchanged.	Set
Unlock	Removes a restriction that Lock put on a record or byte range.	File I/O Functions
Unsigned	Integer data type modifier.	Standard Data Types
Until	Conditional clause used in Do..Loop statements.	Miscellaneous Keywords
Unwrap	Removes one surrounding pair of quotes or delimiters, if both are there.	String Library
UseCount	Returns how many SharedPtr handles share the object.	Smart Pointers
User Defined Types		User Defined Types
User Input (Runtime Library)	Statements and procedures (from runtime library) that get input from the user.	User Input (Runtime Library)
User Input Functions (Graphics Library)	Procedures (from graphics library) for working with mice, gaming devices and keyboards.	User Input Functions (Graphics Library)
UShort	Standard data type: 16 bit unsigned. Equivalent to Unsigned Short.	Standard Data Types
Using (Namespaces)	Brings namespace symbols into the current scope.	Modularizing
UString		UString

V

Name	What it does	Category
va_arg	Returns the current argument from a variable argument list.	Procedures
va_first	Returns a pointer to the first argument in a variable argument list.	Procedures
va_next	Returns a pointer to the next argument in a variable argument list.	Procedures
Val	Converts text to a double.	Converting Data Types
ValInt	Converts text to a 32-bit integer.	Converting Data Types
ValLng	Converts text to a 64-bit integer.	Converting Data Types
Value		For Each
Value	Returns the value by reference; raises an error if the Optional is empty.	Optional
Value	Returns the value by reference; raises an error if the Result failed.	Result
ValueOr	Returns the value, or the fallback you pass if the Optional is empty.	Optional
ValueOr	Returns the value, or the fallback you pass if the Result failed.	Result
Values	Returns a copy of all the values as an Array, in no particular order.	Map
ValUInt	Converts text to an unsigned 32-bit integer.	Converting Data Types
ValULng	Converts text to an unsigned 64-bit integer.	Converting Data Types
Var	Declares a variable whose type is implied from the initializer expression.	Variable Declarations
Variable Declarations	Statements to declare and allocate space for variables.	Variable Declarations
Variance	Returns the sample variance of an array, dividing by n-1.	Math Library
VariancePopulation	Returns the population variance of an array, dividing by n.	Math Library
VerifySet	Returns the position of the first character not in a set, or 0 if all are.	String Library
View (Graphics)	Sets the rectangle that drawing is clipped to, or resets it to the whole screen.	Screen Functions
View Print	Limits printing and scrolling to a range of rows, or to the whole screen again.	Console Functions
Virtual	Declare virtual methods.	User Defined Types
VolumeInfo.FileSystem	Returns the file system's name, such as NTFS or ext4, or an empty string.	Filesystem
VolumeInfo.IsCaseSensitive	Returns true if names on this volume are case-sensitive.	Filesystem
VolumeInfo.IsReadOnly	Returns true if the whole volume is read-only.	Filesystem
VolumeInfo.MaxComponentLen	Returns the longest file or folder name the volume allows, not the longest path.	Filesystem
VolumeInfo.Name	Returns the volume's label, which may be empty and always is on Linux and macOS.	Filesystem
VolumeInfo.RootPath	Returns where the volume is mounted, such as C:\ or /.	Filesystem
VolumeInfo.SupportsLinks	Returns true if the volume can hold symbolic links; false is certain, true a best guess.	Filesystem

W

Name	What it does	Category
Wait	Reads from a hardware port with a mask.	Miscellaneous Keywords
Wait	Waits until the work outstanding reaches zero.	Goroutines and Channels
WaitFor	Waits at most ms milliseconds for the work to reach zero; returns false on a timeout.	Goroutines and Channels
WalkDir	Lists every entry under a folder, subfolders included, for a for each loop.	Filesystem
WalkIterator	Holds the iterator WalkDir hands out, for stepping through a walk without for each.	Filesystem
WalkOptions.FollowSymlinks	Chooses whether a walk enters linked folders; false by default, so it cannot loop.	Filesystem
WalkOptions.IncludeHidden	Chooses whether a walk returns hidden entries; true by default.	Filesystem
WalkOptions.MaxDepth	Limits how deep a walk goes: 1 is the immediate children, 0 (the default) no limit.	Filesystem
WalkOptions.StopOnError	Chooses whether a walk ends at its first error; false by default, so it carries on.	Filesystem
WalkOptions.YieldDirectories	Chooses whether a walk returns folders as well as files; true by default.	Filesystem
WallClock.Now	Returns the local date and time, with the UTC offset in force at this moment.	Date and Time (Chrono)
WallClock.Resolution	Returns the smallest step the wall clock reports, as a TimeSpan.	Date and Time (Chrono)
WallClock.TimeOfDay	Returns the current local time of day as a LocalTime.	Date and Time (Chrono)
WallClock.Today	Returns today's local date as a LocalDate.	Date and Time (Chrono)
WallClock.UtcNow	Returns the current moment on the UTC timeline, read from the system clock.	Date and Time (Chrono)
Warn	Logs a message at the warn level, or returns a record to add fields to.	Logging
WBin	Returns a number as binary wide-string text.	String Functions
WChr	Returns a wide string made from one or more Unicode code points.	String Functions
WeakPtr	Holds a link to a shared object that does not keep it alive, to break cycles.	Smart Pointers
Weekday	Returns the day of the week, 1 to 7, counting from Sunday unless told otherwise.	Date and Time Functions
WeekdayName	Returns the name of a weekday number in the system's language, or its abbreviation.	Date and Time Functions
Wend (Or 'End While')	Control flow statement.	Miscellaneous Keywords
WHex	Returns a number as hexadecimal wide-string text.	String Functions
While	Control flow statement.	Miscellaneous Keywords
While...Wend (Or 'While...End While')	Control flow statement for looping.	Control Flow Statements
Width	Sets or returns the number of columns and rows of the console.	Console Functions
Window	Sets the coordinate system mapped onto the current view.	Screen Functions
WindowTitle	Sets the title of the graphics window.	Screen Functions
Winput()	Reads a number of wide characters from a file or device and returns them.	User Input (Runtime Library)
With	Statement block to allow implicit access to fields in a user defined type variable.	User Defined Types
WithCancel	Returns a child context that you cancel yourself.	Goroutines and Channels
WithField	Returns a child logger that adds one field to every record it makes.	Logging
WithName	Returns a child logger with its own component name and the parent's sinks.	Logging
WithTimeout	Returns a child context that cancels itself after the given milliseconds.	Goroutines and Channels
WOct	Returns a number as octal wide-string text.	String Functions
WorkerCount	Returns how many OS threads the scheduler is running goroutines on.	Goroutines and Channels
Wrap	Surrounds the string with quotes or a given pair of delimiters.	String Library
Write	Writes values separated by commas, with strings in double quotes.	Console Functions
Write #	Writes values to a file as comma-separated text, strings in quotes, for Input # to read.	File I/O Functions
Write (File Access)	Opens a Binary or Random file for writing only; an existing file is emptied first.	File I/O Functions
WriteAllBytes	Writes an Array of bytes to a file, creating the file or replacing it.	Filesystem
WriteAllText	Writes a string to a file as UTF-8, creating the file or replacing it.	Filesystem
WriteAtomic	Replaces a file so a reader sees the old or the new contents, never a half-written file.	Filesystem
WSpace	Returns a wide string of n spaces.	String Functions
WStr	Returns a number as a wide string.	Converting Data Types
WString	Standard data type: wide character string.	Standard Data Types
Wstring (Function)	Returns a wide string of n copies of one character.	String Functions

X

Name	What it does	Category
Xor (Graphics Put)	Combines source and destination pixels with a bitwise Xor, as a Put method.	2D Drawing Functions

Y

Name	What it does	Category
Year	Returns the year of a date serial.	Date and Time Functions

Z

Name	What it does	Category
ZString	Standard data type: 8 bit character string.	Standard Data Types

Other

Name	What it does	Category
... (Ellipsis)		Procedures
2D Drawing Functions	Statements and procedures for working with 2D graphics.	2D Drawing Functions
DATE	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
DATE_ISO	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
__Fastcall	Specifies the Fastcall calling convention in a procedure declaration.	Procedures
FB_64BIT	Intrinsic define set by the compiler.	Intrinsic Defines
FB_ANDROID	Intrinsic define set by the compiler.	Intrinsic Defines
FB_ARG_COUNT	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_ARG_EXTRACT	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_ARG_LEFTOF	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
Fb_Arg_Listexpand	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_ARG_RIGHTOF	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_ARGC	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_ARGV	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_ARM	Intrinsic define set by the compiler.	Intrinsic Defines
FB_ASM	Intrinsic define set by the compiler.	Intrinsic Defines
FB_BACKEND	Intrinsic define set by the compiler.	Intrinsic Defines
FB_BIGENDIAN	Intrinsic define set by the compiler.	Intrinsic Defines
FB_BUILD_DATE	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_BUILD_DATE_ISO	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_BUILD_FORK_ID	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_BUILD_SHA1	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_CYGWIN	Intrinsic define set by the compiler.	Intrinsic Defines
FB_DARWIN	Intrinsic define set by the compiler.	Intrinsic Defines
FB_DOS	Intrinsic define set by the compiler.	Intrinsic Defines
FB_ERR	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_EVAL	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_FPMODE	Intrinsic define set by the compiler.	Intrinsic Defines
FB_FPU	Intrinsic define set by the compiler.	Intrinsic Defines
FB_FREEBSD	Intrinsic define set by the compiler.	Intrinsic Defines
FB_GCC	Intrinsic define set by the compiler.	Intrinsic Defines
FB_GUI	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_IIF	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_JOIN	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_JS	Intrinsic define set by the compiler.	Intrinsic Defines
FB_LANG	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_LINUX	Intrinsic define set by the compiler.	Intrinsic Defines
FB_MAIN	Intrinsic define set by the compiler.	Intrinsic Defines
FB_MIN_VERSION	Macro function to test minimum compiler version.	Intrinsic Defines
TIKO_COMPILER		TIKO_COMPILER
FB_MT	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_NETBSD	Intrinsic define set by the compiler.	Intrinsic Defines
FB_OPENBSD	Intrinsic define set by the compiler.	Intrinsic Defines
FB_OPTIMIZE	Intrinsic define set by the compiler.	Intrinsic Defines
FB_OPTION_BYVAL	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_DYNAMIC	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_ESCAPE	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_EXPLICIT	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_GOSUB	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_PRIVATE	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OPTION_PROFILE	Intrinsic define set by the compiler.	Intrinsic Defines
FB_OUT_DLL	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OUT_EXE	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OUT_LIB	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_OUT_OBJ	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_PCOS	Intrinsic define set by the compiler.	Intrinsic Defines
FB_PPC	Intrinsic define set by the compiler.	Intrinsic Defines
FB_PROFILE	Intrinsic define set by the compiler.	Intrinsic Defines
Fb_Query_Symbol	Intrinsic define (macro) performed by the compiler, and its associated sub-macros.	Intrinsic Defines
FB_QUOTE	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_SIGNATURE	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_SSE	Intrinsic define set by the compiler.	Intrinsic Defines
FB_UNIQUEID	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_UNIQUEID_POP	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_UNIQUEID_PUSH	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_UNIX	Intrinsic define set by the compiler.	Intrinsic Defines
FB_UNQUOTE	Intrinsic define (macro) performed by the compiler.	Intrinsic Defines
FB_VECTORIZE	Intrinsic define set by the compiler.	Intrinsic Defines
FB_VER_MAJOR	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_VER_MINOR	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_VER_PATCH	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
FB_VERSION	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FB_WIN32	Intrinsic define set by the compiler.	Intrinsic Defines
FB_X86	Intrinsic define set by the compiler.	Intrinsic Defines
FB_XBOX	Intrinsic define set by the compiler.	Intrinsic Defines
FILE	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FILE_NQ	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FUNCTION	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
FUNCTION_NQ	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
LINE	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines
PATH	Intrinsic define (macro string) set by the compiler.	Intrinsic Defines
__Thiscall	Specifies the Thiscall calling convention in a procedure declaration.	Procedures
TIME	Intrinsic define (macro value) set by the compiler.	Intrinsic Defines