Getting Started

Getting Started

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Running the Interpreter

nubasic                   # interactive REPL
nubasic myprogram.bas     # load and run a file
nubasic -e myprogram.bas  # alternative: exec from command line

The interactive REPL (Read-Eval-Print Loop) accepts both single statements and complete programs. You can type a statement and press Enter to execute it immediately, or enter numbered lines to build up a program in memory and then type RUN.

Your First Program

Type directly in the REPL or save to a .bas file:

Print "Hello, world!"

With line numbers (classic BASIC style):

10 Print "Hello, world!"
20 End

Line numbers are entirely optional. Modern nuBASIC programs omit them and use structured control flow instead. The two styles can coexist — nuBASIC accepts a mix of numbered and unnumbered lines in the same source file.

Comments begin with a single quote ' or the keyword Rem:

' This is a comment
Rem This is also a comment
Print "Hello"   ' inline comment

Multiple statements can appear on a single line separated by a colon:

x% = 5 : y% = 10 : Print x% + y%

Shebang (Linux/macOS)

Make a .bas file directly executable on Unix-like systems by adding a shebang line as the very first line of the file:

#!/usr/local/bin/nubasic
Print "Hello from a script!"

Then mark the file as executable: chmod +x myscript.bas && ./myscript.bas

Built-in Help

The REPL includes a complete built-in help system. You never need to leave the interpreter to look up a keyword:

Help               ' list all keywords grouped by category
Help Print         ' full description and syntax of Print
Help ScreenLock    ' description of the ScreenLock instruction
Help examples      ' list installed example programs with load/run hints
Apropos mouse      ' search all help descriptions for the word "mouse"

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