# If there is a break/continue and is associated with `escapemark`, then return true and clear the mark.
	# If there is no break/continue or if `escapemark` is null then return false.
	# Use this function to catch a potential break/continue.
	fun is_escape(escapemark: nullable EscapeMark): Bool
	do
		if escapemark != null and self.escapemark == escapemark then
			self.escapemark = null
			return true
		else
			return false
		end
	end