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List:       pykde
Subject:    Re: [PyQt] QPointF comparison is kinda wrong
From:       Florian Bruhin <me () the-compiler ! org>
Date:       2015-06-30 11:26:28
Message-ID: 20150630112627.GQ22364 () tonks
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* Arseniy Terekhin <senyai@gmail.com> [2015-06-30 13:38:38 +0300]:
> Windows 7, python 2.7.10, PYQT_VERSION_STR = '4.11.4'
> 
> >>> from PyQt4.QtCore import QPointF as p
> >>> p() < p()
> True
> >>> p() < p()
> False
> [...]

That's not anything specific to PyQt - it's just how Python 2
(unfortunately) implements comparing of incomparable types - it uses
their identity (id()) if they are of the same type:

    >>> class Foo(object): pass
    ...
    >>> Foo() < Foo()
    True
    >>> Foo() < Foo()
    True
    >>> Foo() < Foo()
    False
    >>> Foo() < Foo()
    True
    >>> Foo() < Foo()
    False

On Python 3, you get a much more sensible result:

    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    TypeError: unorderable types: QPointF() < QPointF()

Needless to say, I recommend switching to Python 3 ;)

Florian

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