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lilbobbytables on June 1, 2017 | parent | context | favorite | on: Hunting Performance in Python Code: Measuring Memo...

Localizing append helps, but that's not all of it:

Building a list of 10,000,000 items:

List comprehension: 599ms For loop: 930ms For loop with append localized: 736ms

dom0 on June 2, 2017 [–]

Comprehensions have their own opcodes which directly call e.g. PyList_Append with no further checks or lookups in each iteration.

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