On Aug 29, 2019, at 16:32, Guido van Rossum <gu...@python.org> wrote: > > Surely the meaning of `?` in a programming language also has to be learned. > And not every language uses it to mean "optional" (IIRC there's a language > where it means "boolean" -- maybe Scheme?)
Sure, ? does mean lots of different things that have nothing to do with Optional. The C ?: operator is probably the most famous. But as an operator on types, I can’t think of any uses other than Optional. But, just for fun: * ?: from C * null-coalescing, as in C# * Optional-chaining, as in Swift * throwing, as in Rust *’ordinary identifier character, usually idiomatically predicate functions end in ?, as in Scheme * ordinary operator (as opposed to identifier) character, used for a wide variety of completely unrelated monad things you don’t want to know about, as in Haskell * special 1-char identifier that’s idiomatically sort of like _ from C/gettext, as in Smalltalk * expand as macro, as in… Erlang? * print, as in Basic * random, as in APL * whatever the hell Ruby is doing that gives me "P" in one interpreter and 80 in another when I type ?P. Ruby _also_ has ? as an id-cont character, with the Schemeish convention, and the ?: operator, and in some other contexts it’s a syntax error but in some it does… whatever that string-or-ord thing is. _______________________________________________ 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/JCMN56E2BP4G6FL4KAOFIPQ66AZB5RDG/ Code of Conduct: http://python.org/psf/codeofconduct/
