5.20 break

The break keyword leaves the control flow of the innermost loop (for or while) it is declared in, stopping further iterations:

while(true) {
	expression1;
	if (condition) break;
	expression2;
}

Here, expression1 is evaluated for each iteration, but as soon as condition holds, expression2 is not evaluated anymore.

The typer ensures that it appears only within a loop. The break keyword in switch cases is not supported in Haxe.