On Fri, Apr 9, 2021 at 6:09 PM Stéfane Fermigier <[email protected]> wrote: > > I think the best alias for "empty set" would be the Unicode character "Empty > set" or U+2205, i.e. "∅". > > Alas, it's not a valid identifier in Python: > > >>> ∅ = set() > File "<stdin>", line 1 > ∅ = set() > ^ > SyntaxError: invalid character '∅' (U+2205) > > It works with the similarly looking "ϕ" or 'GREEK PHI SYMBOL' (U+03D5) > > >>> ϕ = set() > >>> ϕ.union({1,2}) > {1, 2} > > But it's less than ideal. > > I think it's an error from the Unicode standard to list the empty set as a > "Mathematical Operator" > (https://en.wikipedia.org/wiki/Mathematical_operators_and_symbols_in_Unicode#Mathematical_Operators_block) > and not as a > "Letterlike Symbol" like ℝ or ℕ > (https://en.wikipedia.org/wiki/Mathematical_operators_and_symbols_in_Unicode#Letterlike_Symbols_block). > > Ex: > > >>> ℕ = [0, ...] # Whatever that means... > >>> ℕ > [0, Ellipsis] > > So yes, the language would need to be changed to allow the proper empty set > unicode symbol to be used. >
Not to mention everyone's keyboards. Python != APL. Err, I mean, Python ≠ APL. ChrisA _______________________________________________ Python-ideas mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/[email protected]/message/TXKHZY6L3CE22XVK3MJTSW2LVGBOIBG5/ Code of Conduct: http://python.org/psf/codeofconduct/
