enum Suit: String { case spades = "♠" case hearts = "♥" case diamonds = "♦" case clubs = "♣" } 例如,我该怎么做: for suit in Suit { // do something with suit print(suit.rawValue) } 结果示例: ♠ ♥ ♦ ♣
我想知道将生成器函数的结果传递给python的enumerate()时会发生什么。例: def veryBigHello(): i = 0 while i < 10000000: i += 1 yield "hello" numbered = enumerate(veryBigHello()) for i, word in numbered: print i, word 枚举是延迟进行的迭代,还是将所有内容都拖入了第一个?我99.999%的人肯定它是惰性的,所以我可以将它与生成器函数完全一样对待,还是需要注意任何事情?
这些Python列表推导的R等效项是什么: [(i,j) for i,j in zip(index, Values)] [(i,j) for i,j in enumerate(Values)] [(i,j) for i,j in enumerate(range(10,20))] %MWE, indexing or enumerating to %keep up with the index, there may %be some parameter to look this up 输出示例 >>> [(i,j) for i,j in enumerate(range(10,20))] [(0, 10), (1, 11), (2, 12), (3, …