Basic Syntax.md

This is a basic primer in Tack's syntax, not an in-depth explanation. For a formal grammar, see formal.ebnf.

Every Tack file must start with a mod statement. For an explanation of the module system, see [[Modules]]. mod path.to.module;

Function declarations

func func_name(arg1: Type1, arg2: Type2) RetType {
	
}

Statements

Tack doesn't have many statements, as it's a mostly expression-based language. However, it does have statements for variable declarations and assignments:

let s = 5;
s = 1;

Expressions

In Tack, most things are expressions.

Operations

5 + 2;
1 - 3;
2 * 5;
3 / 1;

Function calls

function(arg1, arg2);

If statements

if cond {
	function();
}

Blocks in if statements (not if-else statements) must evaluate to void.

If-else statements

if cond {
	function()
} else {
	other_function()
}

Blocks in if-else statements must evaluate to the same type.

While loops

while cond {
	function();
}

Blocks in while loops also must evaluate to void.

For loops

for i in iter {
	function();
}

Tack has Rust-like iterators, and uses them inside for loops. Blocks in while loops also must evaluate to void.