use exclam (!) syntax for factorial in python

Question

Can a working factorial function/operator be defined with a syntax like in mathematics? i.e. using the ! symbol.

I can't think of any use cases of the existing symbol where things could be ambiguous

ipython !shell_escape always has the bang at the start of a line
something like 0!=1 would be True as usual because the other interpretation of factorial(0) = 1 would be SyntaxError: can't assign to literal or similar error)

score 7 · Accepted Answer · answered Aug 14 '11 at 13:05

If you mean, "can I define the ! operator in my Python program?," the answer is no, Python doesn't have a bang operator that can be defined.

If you mean, "could Python be extended to include a ! operator?," the answer is yes, though probably not as a postfix operator like x!. I very much doubt that the Python community would agree it was a good idea and move ahead with it though.

score 6 · Answer 2 · edited May 23 '17 at 09:59

6

You can not define new operators in Python. Instead, either provide a factorial function or simply use math.factorial.

edited May 23 '17 at 09:59

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answered Aug 14 '11 at 13:02

phihag

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use exclam (!) syntax for factorial in python

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