Further Syntax

import

The input instruction is used to incorporate further source files into the program. The syntax is:

import "sys/stdio.asm"
import "sys/comm.c"
import "myfile.c"

The file extension ('c' or 'asm') must also be specified, as well as the pathname (like 'sys/' or 'lib/'). A program can be structured in several files. In this case the "main" file has to import the other files.

Comments

A comment starts with a slash asterisk /* and ends with a asterisk slash */ and can be anywhere in your program. Comments can span several lines within your program.

The compiler supports also single line comments. All characters after the // slashes are ignored by the compiler.

/*
 * this is a comment
 */

// this is a comment
func init() {
}

/* this is a comment */
func loop() { // this is also a comment
}

; (semicolon)

Used to end a statement.

Example

var a = 13;

Notes and Warnings

Forgetting to end a line in a semicolon will result in a compiler error. The error text may be obvious, and refer to a missing semicolon, or it may not. If an impenetrable or seemingly illogical compiler error comes up, one of the first things to check is a missing semicolon, in the immediate vicinity, preceding the line at which the compiler complained.

{} (curly braces)

Curly braces (also referred to as just "braces" or as "curly brackets") are a major part of the mC programming language. They are used in several different constructs, outlined below, and this can sometimes be confusing for beginners. An opening curly brace { must always be followed by a closing curly brace }. This is a condition that is often referred to as the braces being balanced.

Unbalanced braces can often lead to cryptic, impenetrable compiler errors that can sometimes be hard to track down in a large program. Because of their varied usages, braces are also incredibly important to the syntax of a program and moving a brace one or two lines will often dramatically affect the meaning of a program.

Example

The main uses of curly braces are listed in the examples below.

Functions

func myfunction(argument) {
  // any statement(s)
}

Loops

while (boolean expression) {
  // any statement(s)
}

for (initialisation; termination condition; incrementing expr) {
  // any statement(s)
}

Conditional Statements

if (boolean expression) {
  // any statement(s)
}

else if (boolean expression) {
  // any statement(s)
}
else {
  // any statement(s)
}

_asm_ (inline assembler)

The compiler allows inline assembler.

Example for a function with ASM code.

func time_slot(cycle) {
  _asm_ {
    move A, [SP+1]
    add  A, #1
    xor  A, [SP+1]
    msb  A, A
    dec  A
  }
}

• The return value must be provided in register A (the instruction ret is provided by the C function framework)
• For a function foo(a), parameter a is on stack position [SP+1]
• For a function foo(a, b), the parameter a is on the stack position [SP+2] and the parameter b is on the stack position [SP+1]
• For a function foo(a,b,c), the parameter a is on the stack position [SP+3], the parameter b is on the stack position [SP+2] and the parameter b is on stack position [SP+1]