On Tue, Nov 25, 2003 at 08:55:05PM -0800, Jim Dukarm wrote:
> ---------- Martin Maney: --------------
> > It's a nasty, inconsistent gimmick, IMO.  Or does it allow for
> > consistent use of the trailing underscore even with non-keywords?
>
> I wonder whether it is even necessary to avoid the word "class" in
> this context, since it is just being used as a dict key and eventually
> gets included in a stream of text.

As a dict key, no, of course not - then it's just a string.  The
context here was using the lazy shorthand trick for writing a literal
dict without quotation marks, as you showed later.  But this has a
problem with keywords exactly because it doesn't use string literals:

def make_dict(**kw):
    return kw

>>> make_dict(foo=1, bar=2)
{'foo': 1, 'bar': 2}
>>> make_dict(foo=1, bar=2, class=3)
  File "", line 1
    make_dict(foo=1, bar=2, class=3)
                                ^
SyntaxError: invalid syntax

Hence the work-around:

>>> make_dict(foo=1, bar=2, class_=3)
{'class_': 3, 'foo': 1, 'bar': 2}

All of which looks like a stupidly clever hack to me, and the need to
decorate the names with underscores to sidestep keywords highlights the
marginality of the gain.  This is not the one [obvious] way to write a
dictionary literal!

> > Lovely idea, but it seems to require more than just 2.2:
>
> You have a point there.

For some reason I didn't think to check the 2.3 library reference until
after sending that off; there it says that the keyword hack was added
in 2.3.

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