[Python-Dev] dict(keys, values)

[Jim Jewett]

George Sakkis wrote:

> far too often I use the idiom dict(zip(keys,values)), or
> the same with izip. How does letting dict take two positional
> arguments sound ?

I think the dict constructor is already a bit too complicated, and
would prefer that it be a separate classmethod, such as

    dict.zip(keys, values=itertools.repeat(None))

The default argument on values should finish the replacement of
dict.fromkeys functionality that sets and defaultdicts began.

> At least as efficient as the current alternatives.

I think it has to do better (at least by eliminating the temporary zip
object) to be worthwhile; the do-it-yourself alternative is pretty
short.

    >>> # from itertools import izip as zip
    >>> def dictz(keys, values):  return dict(zip(keys,values))

-jJ