4 ms·

Python actually discourages using map anf filter. Which is kind of weird to me but whatever.

• nerdponx 9y ago
  Well in some cases it really is more efficient. [func(x) if x in collection if cond(x)] makes a single pass over the data and gives you a list, but list(map(func, filter(cond, collection))) makes two passes and requires some extra function calls. I think the real reason is perceived legibility on the part of the Python core devs. I seem to recall a document from a while ago in which GvR himself came out in favor of list comprehension style. "Explicit is better than implicit".
  • nitroll 9y ago
    Both map and filter returns an iterator, so you only iterate once when creating the list.