Hi friends,

I am meanwhile the PySide maintainer at The Qt Company,
and we are trying to make the mapping from Qt functions
to Python functions as comparable as possible.

One problem are primitive pointer variables:
In Qt, it is natural to use "sometype *varname" to make a
mutable variable. In Python, you have to turn such a thing
into a result-tuple. Example:

    void QPrinter::getPageMargins(qreal *left, qreal *top, \
        qreal *right, qreal *bottom, QPrinter::Unit unit) const

(meanwhile deprecated, but a good example)

is mapped to the Python signature

    def getPageMargins(self, \
        unit: PySide2.QtPrintSupport.QPrinter.Unit) \
        -> typing.Tuple[float, float, float, float]: ...

NOW my question:
----------------

I would like to retain the variable names in Python!
The first idea is to use typing.NamedTuple, but I get the impression
that this would be too much, because I would not only need to create
an extra named tuple definition for every set of names, but also
invent a name for that named tuple.

What I would like to have is something that looks like

    def getPageMargins(self, \
        unit: PySide2.QtPrintSupport.QPrinter.Unit) \
        -> typing.NamedTuple[left: float, top: float, \
                             right:float, bottom:float]: ...

but that is obviously not a named tuple.
Possible would be to derive a name from the function, so maybe
a definition could be used like

class PageMargingResult(NamedTuple):
    left: float
    top: float
    right: float
    bottom: float

but then I would have some opaque PageMargingResult type. This would
work, but as said, this is a bit too much, since I only
wanted something like a tuple with names.

What do you suggest to do here? Something what I am missing?

Cheers -- Chris
--
Christian Tismer             :^)   tismer@stackless.com
Software Consulting          :     http://www.stackless.com/
Karl-Liebknecht-Str. 121     :     https://github.com/PySide
14482 Potsdam                :     GPG key -> 0xFB7BEE0E
phone +49 173 24 18 776  fax +49 (30) 700143-0023



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