#19597: General code cleanup: avoid code like x.__eq__(y)
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Reporter: jdemeyer | Owner:
Type: enhancement | Status: needs_review
Priority: major | Milestone: sage-6.10
Component: misc | Resolution:
Keywords: | Merged in:
Authors: Jeroen Demeyer | Reviewers:
Report Upstream: N/A | Work issues:
Branch: | Commit:
u/jdemeyer/general_code_cleanup__avoid_x___eq___y_|
b2094a8a1cedafab73db0ed7653db3112982cec4
Dependencies: | Stopgaps:
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Comment (by jdemeyer):
Replying to [comment:9 vdelecroix]:
> `groups/perm_gps/permgroup.py`: Is there any difference between
`list(L)` and `[x for x in L]`? As far as I understand `list` is smarter
and call for `__len__` to allocate directly the right amount of memory.
Whereas the second uses `.append`.
That's true in general, however: there is no `__len__` implemented in this
case. There is a generic `__len__` coming from `Parent` but that calls
`len(self.list())` which would lead to an infinite loop. So I think that
`[x for x in L]` is the most efficient way to create the list here.
That's probably also the reason the old code was written like
`list(self.__iter__())` and not `list(self)`.
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Ticket URL: <http://trac.sagemath.org/ticket/19597#comment:11>
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