So this would make `a` a new keyword. I don't think that could be added into python 4 at the earliest because it would immediately break all code for which `a` is a variable name.
I can appreciate wanting to make simple operations easy to read, though I think this relies too much on understanding English and wouldn't be intuitive for people who aren't English speaking. I am native English speaking so I wouldn't know for sure, but I think accepting that "or" is the same as "||" is an easier jump to make than "x is a y" being a construct for indicating that x belongs to the y class. If you need this English-style syntax, I believe `type(x) is y` is guaranteed to be True if x is exactly of the y type and not one of its super classes. On Fri, May 1, 2020, 1:27 PM gbs--- via Python-ideas < python-ideas@python.org> wrote: > In cases where it makes sense to do explicit type checking (with ABCs or > whatever), I really detest the look of the isinstance() function. > > if isinstance(thing, Fruit) and not isinstance(thing, Apple): > > Yucky. > > What I really want to write is: > > if thing is a Fruit and thing is not an Apple: > > and after thinking about it on and off for a while I wonder if it might > indeed be possible to teach the parser to handle that in a way that > eliminates almost all possible ambiguity with the regular "is", including > perhaps 100% of all existing standard library code and almost all user code? > > Maybe this has been considered at some point in the past? The "is [not] > a|an" proposal would at least be a strong contender for "hardest thing to > search for on the internet" lol. > > Thanks! > > Gavin > _______________________________________________ > 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/YKLNQXONLLZ7OXEMUHXF5HD4PCX4SNVT/ > Code of Conduct: http://python.org/psf/codeofconduct/ >
_______________________________________________ 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/PQSJ6PSRS3JZZUV7CRRKRSGJAPVBYP6G/ Code of Conduct: http://python.org/psf/codeofconduct/
