[PyQt] Floats accepted for C++ ints?
me at the-compiler.org
Tue Jul 5 23:07:30 BST 2016
* Phil Thompson <phil at riverbankcomputing.com> [2016-07-05 22:18:16 +0100]:
> On 5 Jul 2016, at 9:51 pm, Florian Bruhin <me at the-compiler.org> wrote:
> > * Phil Thompson <phil at riverbankcomputing.com> [2016-07-05 18:33:37 +0100]:
> >> On 5 Jul 2016, at 6:22 pm, Florian Bruhin <me at the-compiler.org> wrote:
> >>> I've noticed Python floats are accepted when a C++ int is expected,
> >>> and simply truncated:
> >>> >>> from PyQt5.QtCore import QRect
> >>> >>> QRect(0.5, 0.5, 0.5, 0.5)
> >>> PyQt5.QtCore.QRect()
> >>> >>> QRect(1.5, 1.5, 1.5, 1.5)
> >>> PyQt5.QtCore.QRect(1, 1, 1, 1)
> >>> Is this intended behaviour? I'd have expected to raise a TypeError
> >>> (or, if anything, accept floats where .is_integer() is true)
> >> It's standard Python behaviour. Floats implement __int__().
> > They also implement __str__, yet I obviously can't use them where Qt
> > expects a QString ;)
> > Isn't __int__ just there to customize what should happen when using
> > int(), just like __str__ is for str()?
> > float is not a subclass of int (i.e. isinstance(1.5, int) == False),
> > which is why this not raising a TypeError confuses me.
> It's how PyLong_AsLong() works...
Fair enough - I guess you could call PyLong_Check() on it first
("Return true if its argument is a PyLongObject or a subtype of
PyLongObject"), but it might also be too late to do that now?
http://www.the-compiler.org | me at the-compiler.org (Mail/XMPP)
GPG: 916E B0C8 FD55 A072 | http://the-compiler.org/pubkey.asc
I love long mails! | http://email.is-not-s.ms/
-------------- next part --------------
A non-text attachment was scrubbed...
Size: 819 bytes
Desc: not available
More information about the PyQt