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Comprehension to Generator

Sourcery refactoring id: comprehension-to-generator


Replace unneeded comprehension with generator


hat_found = any([is_hat(item) for item in wardrobe])


hat_found = any(is_hat(item) for item in wardrobe)


Functions like any, all and sum allow you to pass in a generator rather than a collection. Doing so removes a pair of brackets, making the intent slightly clearer. It will also return immediately if a hat is found, rather than having to build the whole list. This lazy evaluation can lead to performance improvements.

Note that we are actually passing a generator into any() so strictly speaking the code would look like this:

hat_found = any((is_hat(item) for item in wardrobe))

but Python allows you to omit this pair of brackets.

The standard library functions that accept generators are:

"all", "any", "enumerate", "frozenset", "list", "max", "min", "set", "sum", "tuple"