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Whitespace and spelling fixes.

This commit is contained in:
Alex Gaynor 2012-07-29 18:10:33 -07:00
parent 162406d485
commit 9962846ad1
1 changed files with 5 additions and 3 deletions
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pep-0424.txt
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@ -28,8 +28,9 @@ interpreter and non-standard library Python to implement.
``__length_hint__`` must return an integer (else a TypeError is raised) or
``NotImplemented, and is not required to be accurate. It may return a value
that is either larger or smaller than the actual size ofthe container. A return value of ``NotImplemented`` indicates that there is no finite length estimate.
It may not return a negative value (else a ValueError is raised).
that is either larger or smaller than the actual size of the container. A
return value of ``NotImplemented`` indicates that there is no finite length
estimate. It may not return a negative value (else a ValueError is raised).
In addition, a new function ``operator.length`` hint is added, having the
follow semantics (which define how ``__length_hint__`` should be used::
@ -66,7 +67,8 @@ return value for objects which do not provide a length or length hint.
Rationale
=========
Being able to pre-allocate lists based on the expected size, as estimated by ``__length_hint__``, can be a significant optimization. CPython has been
Being able to pre-allocate lists based on the expected size, as estimated by
``__length_hint__``, can be a significant optimization. CPython has been
observed to run some code faster than PyPy, purely because of this optimization
being present.