pairs.py 文件源码

def __getitem__(self, pair):
        fg, bg = pair
        assert isinstance(fg, int) and -1 <= fg < 256
        assert isinstance(bg, int) and -1 <= bg < 256

        if pair in self.pair_numbers:
            # If pair is stored, retrieve it.
            return curses.color_pair(self.pair_numbers[pair])
        elif self.counter < MAX_PAIRS:
            # If we still haven't filled our queue, add the new pair.
            curses.init_pair(self.counter, fg, bg)
            self.pair_numbers[pair] = self.counter
            self.counter += 1
            return curses.color_pair(self.counter - 1)
        else:
            # If the queue is full, pop the oldest one out
            # and use its pair number to create the new one.
            _, oldest = self.pair_numbers.popitem(last=False)
            curses.init_pair(oldest, fg, bg)
            self.pair_numbers[pair] = oldest
            return curses.color_pair(oldest)