src/source/location_stack.ghul

1		namespace Source is
2		class LOCATION_STACK is
3		_stack: Collections.STACK[LOCATION];
4
5		init() is
6		_stack = Collections.STACK[LOCATION]();
7		si
8
9		is_empty: bool => _stack.count == 0;
10
11		current: LOCATION? =>
12		if _stack.count > 0 then
13		_stack.peek();
14		else
15		null;
16		fi;
17
18		push(location: LOCATION) is
19		_stack.push(location);
20		si
21
22		pop() is
23		assert _stack.count > 0;
24		_stack.pop();
25		si
26		si
27		si