On Sun, 18 Apr 2010 23:29:44 -0700, franck wrote: > Dear all, > > I'm wondering why in Python's grammar, keyword arguments are specified > as: > > argument: ... | test '=' test
Where are you finding that? > I would have expected something like > > argument: ... | NAME '=' test > > Indeed, I cannot imagine a case where the keyword is something else than > an identifier. Moreover, in the Python language reference (see > http://docs.python.org/reference/expressions.html#grammar-token- keyword_item) > one can read: > > keyword_item ::= identifier "=" expression > > which is what I was expecting. This tells you that keyword arguments cannot have keywords that aren't identifiers: >>> sum(1=2) File "<stdin>", line 1 SyntaxError: keyword can't be an expression The only thing I can think of is that you're extrapolating from use cases like this: >>> def f(x): ... return x ... >>> x=2 >>> f(x=x) 2 But that's just a special case of this: >>> y=2 >>> f(x=y) 2 Of course, I could be completely misunderstanding what you mean. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
