Nick Coghlan wrote:
> We've also veered fairly far off topic for the Py3k list - further ideas
> for positional-only argument syntax or decorators should probably be
> kicked around on python-ideas rather than here or python-dev.
For a function specification like this:
def f(w, x=1, *, y, z=2): ...
My preference is for w and x to be positional only, w is required; y and
z are keyword only, y is required.
I personally like the idea that for functions like range([start,] stop
[,step]) that the function describes which combinations of positional
functions are allowed. An alternative would be overloading, which I
would use, albeit rarely:
def _range(x, y, z): ...
def range(y): return _range(None, y, None)
def range(x, y): return _range(x, y, None)
def range(x, y, z): return _range(x, y, z)
As for this relative nonsense:
def test([arg1=1, [[*arg2,] arg3=3,]] arg4): ...
Someday I'll dig around in the interpreter enough to make this work,
just to see what it would be like. But not today.
> Another use would be allowing the '_cache trick' with a varargs
> function, i.e.
>
> def f(*args, _cache={}):
> ...
>
> Personally I don't like this trick though...
My preference for defining persistent variables with a local scope would
be to introduce a "local" or "static" keyword like "global":
def f(*args):
static cache={}
...
But I'm sure that that has been discussed before.
Joel
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
