bpo-33234: Add exact allocation optimization to lists in What's New #10200
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Doc/whatsnew/3.8.rst
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| * The :class:`list` constructor does not overallocate the internal item buffer | ||
| if the input iterable has a known size (the input implements ``__len__``). | ||
| This makes the created list 12% smaller on average and it speeds the creation | ||
| of very large lists. (Contributed by Pablo Galindo in :issue:`33234`.) |
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"and it speeds the creation of very large lists" even if it's true, I'm not sure that it's worth it to mention it. The most important part is the memory footprint, no?
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Yup, I will remove that sentence.
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LGTM, but I have a last question :-)
Doc/whatsnew/3.8.rst
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| that arbitrary attributes can no longer be added to them. | ||
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| * The :class:`list` constructor does not overallocate the internal item buffer | ||
| if the input iterable has a known size (the input implements ``__len__``). |
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nitpick: is it "size" or "length"? (len means "length", no?)
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Yup, I used size as the CAPI call is PyObject_Size. Do you prefer to use length ?
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Honestly, it's not important, so it's up to you :-) The doc says "length":
https://docs.python.org/dev/reference/datamodel.html#object.__len__
For me, "size" means more number of bytes, and "length" or "count" the number of items. But I'm used to the C language which is different :-)
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Let's use length as you suggest :)
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https://bugs.python.org/issue33234