[Python-Dev] dict() enhancement idea?

Barry A. Warsaw barry@python.org
Thu, 21 Nov 2002 11:01:17 -0500

>>>>> "JvR" == Just van Rossum <just@letterror.com> writes:

    JvR> But: no, I simply find the {"key": "value"} syntax sometimes
    JvR> inappropriate.  Consider the following example:

Me too, and I have something similar in Mailman.  It's fine that keys
are limited to identifiers (although I did recently have one small
related bug because of this in a mostly unused corner of the code).

    |    # idiom 2
    |    name1 = foo()
    |    name2 = foo()
    |    x = template % locals()
    |    # idiom 3 (after my patch, or with a homegrown function)
    |    x = template % dict(key1=foo(), key2=baz())
    JvR> I find #3 more readable than #1. #2 ain't so bad, but I hate
    JvR> it that when you're quickly going over the code it looks like
    JvR> there are some unused variables.

I go even a step farther than #2 with my i18n idiom, e.g.

    name1 = foo()
    name2 = foo()
    x = _(template)

Where _() does a sys._getframe() and automatically sucks the locals
and globals for interpolation.  Works great, but it gives pychecker
fits. :)

I like both the **kws addition as well as the keywords-as-attributes