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0 pointspcote13y ago0 comments

Using list comprehensions as a replacement for filter and map I can see. I don't really see where you're getting at as far as substitutes for 'reduce' are concerned. For me, the 'operator' module is a justification for using 'reduce', not a replacement for it.

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masklinn13y ago

> I don't really see where you're getting at as far as substitutes for 'reduce' are concerned.

Reduce simply isn't used much in Python code, as a product of both culture and rather lacking lambdas. It's used so little (pretty much the only "usual use case" is covered by `sum`) it's been moved out of the builtins and to the functools module in Python 3 (whereas `map` and `filter` have remained)

untothebreach13y ago

Thank you, that was much more eloquently put than I could have provided. Indeed, `sum` was the one common use case I could think of, so I didn't bother including it as an example. I honestly can't say I miss `reduce` at all when writing python.

masklinn13y ago

> Indeed, `sum` was the one common use case I could think of

There are 4 other not-completely-uncommon cases in the builtins, implemented in a significantly more efficient manner for the latter 2 (ignoring Python v C): min, max, any and all. And map and filter technically but repeatedly concatenating lists together (in python) isn't the most useful way to peg your CPU.

j / k navigate · click thread line to collapse

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masklinn13y ago

> I don't really see where you're getting at as far as substitutes for 'reduce' are concerned.

untothebreach13y ago

masklinn13y ago

> Indeed, `sum` was the one common use case I could think of

j / k navigate · click thread line to collapse