syntax for preset locals without using dummy args with defaults
tjreedy at udel.edu
Sat Jan 11 00:15:00 CET 2003
"Bengt Richter" <bokr at oz.net> wrote in message
news:avmoeu$v8p$0 at 188.8.131.52...
> Yet another idea ;-)
> Right now we often see
> def foo(x, y=default, z=some_expression):
> where the purpose is not to have three parameters, but two
> plus a local binding (z) in foo to the value of some_expression
> evaluated in the def-time environment. z may bind something not
> accessible later at call time, or it may be just to avoid
> an expensive expression at each function call.
> The subject line idea amounts to using the same parameter list
> but not incrementing argcount
+1/2 on idea
(ok, a little more complex, but that's the
> essence) Thus:
> def foo(x, y=default)(z=some_expression):
-1/2 on this syntax. I would prefer ';' instead of ',' to mark end of
run-time variable params and start of define-tine fixed params. Have
no idea how difficult it would be to have compiler differentiate
between this and ';' as statement separator.
>For longer lists of initializations, it is helpful that parens allow
putting things on multiple lines
One set of parens already does this.
Terry J. Reedy
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