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Notes on CPython Lists

• fernly 9y ago
  Hmm. You mention having > ...Another reason to preallocate Python lists when possible. But how would one do that? I mean, you could do `list(range(10000))` which would in a sense pre-allocate a 10000-element list. But, does the `list()` operation look ahead and make a list that size at once, or does it just keep appending the next item from the iterable, going through the 12% expansions multiple times? Also, I can't think offhand of an iterable that would generate N identical "empty" list items. Like 10000 zeros or 10000 Nones. Anyone?
• est 9y ago
  > Creating List slices ... with some sort of copy-on-write semantics https://docs.python.org/3/library/stdtypes.html#memoryview https://docs.python.org/3/library/stdtypes.html#memoryview