The “correct” (according to Bourbaki) mathematical notation for an empty set is “∅" (aka Unicode U+2205, or HTML ∅) Some time ago, for a project which had a lot of empty sets, I tried to use this symbol as a short hand for set(). But:
⦰ = set() File "<stdin>", line 1 ⦰ = set() ^ SyntaxError: invalid character '⦰' (U+29B0) ø = set()
In other words, “⦰” is illegal as an identifier in Python (same for ⌀ aka U+2300 DIAMETER SIGN), but “ø” (aka U+00F8 LATIN SMALL LETTER O WITH STROKE) is legal ! So I used "⌀" instead of “⦰”, but I eventually dropped the whole idea because, IIRC, some tools weren’t too happy with it. Still, I guess it wouldn’t be neither too hard nor two disruptive to accept “⦰” as well as some other mathematical characters as identifiers in Python. Since once of the application domains where Python shines nowadays is mathematics (numerical, but also symbolic), I think it’s a shame that we are preventing to use the proper unicode characters to designate some universal mathematical objects. More info here: https://en.wikipedia.org/wiki/Null_sign S. On 13 Mar 2022 at 22:52:16, joao.p.f.batista.97@gmail.com wrote:
Currently: l = [] # new empty list t = () # new empty tuple s = set() # new empty set (no clean and consistent way of initializing regarding the others) <<< d = {} # new empty dictionary
Possible solution: s = {} # new empty set d = {:} # new empty dictionary (the ":" is a reference to key-value pairs)
Current workaround at least for consistency: l = list() # new empty list t = tuple() # new empty tuple s = set() # new empty set d = dict() # new empty dictionary
However, it doesn't feel right to not be able to initialize an empty set as cleanly and consistently as lists, tuples and dictionaries in both forms. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-leave@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/OPWEKL... Code of Conduct: http://python.org/psf/codeofconduct/
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