17.06.19 17:47, Guido van Rossum пише:
Indeed it would work the same way as set comparison does, if you
interpret a type as the set of its instances.
But I imagine that many Python users are not so familiar with this
abstraction level (even if they use isinstance() and issubclass() all
day long). Sometimes using a *different* operator is helpful to send a
signal to the reader that a *different* kind of thing is being
manipulated -- sort of like how you can tell that a collection is a list
or a set by noticing whether values are added using append() or add().
Type theorists apparently have chosen to use the <: notation, and
presumably for the same reason.
Then perhaps we should start to use <: for sets and left < and <= for
types that support full ordering.
_______________________________________________
Python-ideas mailing list -- python-ideas@python.org
To unsubscribe send an email to python-ideas-le...@python.org
https://mail.python.org/mailman3/lists/python-ideas.python.org/
Message archived at
https://mail.python.org/archives/list/python-ideas@python.org/message/ESNRRGBIHNVFMUJ3YK4RVZSVFXZQW47X/
Code of Conduct: http://python.org/psf/codeofconduct/
