# Push someting in the state stack
	private fun push(numstate: Int, list_node: nullable Object)
	do
		var pos = _stack_pos + 1
		_stack_pos = pos
		if pos < _stack.length then
			var state = _stack[pos]
			state._state = numstate
			state._nodes = list_node
		else
			_stack.push(new State(numstate, list_node))
		end
	end