[Python-ideas] Verbatim names (allowing keywords as names)

[Carl Smith]

> On Tue, May 15, 2018 at 8:41 PM, Steven D'Aprano <steve at pearwood.info>
> wrote:
>
>> Inspired by Alex Brault's  post:
>>
>> https://mail.python.org/pipermail/python-ideas/2018-May/050750.html
>>
>> I'd like to suggest we copy C#'s idea of verbatim identifiers, but using
>> a backslash rather than @ sign:
>>
>>     \name
>>
>> would allow "name" to be used as an identifier, even if it clashes with
>> a keyword.
>
>
I strongly disagree, but can't seem to get anyone
​ to bite.

We want to be able to introduce a keyword that was formally a name, still
allow
it to be used as a name, still allow code that uses it as a keyword to
interoperate
​ ​
with code that uses it as a name
, without changing the language
or implementation
too much.

​Ideally, Python would still not allow the keyword to be used as a name and
a
keyword in the same file??

The lexer could class the tokens as *keynames*, and the parser could use the
context of the first instance of each keyname to determine if it's a name or
keyword for the rest of that file. Projects that used the word as a name
would
only be prevented from also using it as a keyword in the same file.

It's really then a question of whether users could elegantly and naturally
reference a name in another module without introducing the name to the
current module's namespace.

We only reference external names (as syntactic names) in import statements,
as properties after the dot operator, and as keyword arguments.

If code that used the word as a keyword was still allowed to use the word as
a name after the dot operator and as a keyword argument *in an invocation*,
it would only change the language in a subtle way.

If we could reference keynames in import statements, but not import the
name,
so basically allow `from keyname import keyname as name`, but not allow
`import keyname`, we could still easily import things that used the keyname
as a name. This wouldn't change the language too dramatically either.

Maybe I'm just being dumb, but it seems like three subtle changes to the
language would allow for everything we want to have, with only minor
limitations
on the rare occasion that you want to use the new keyword with a library
that is
also using the same keyword as a name.

I promise not to push this idea again, but would really appreciate someone
taking
a couple of minutes to explain why it's not worth responding to. I'm not
offended,
but would like to know what I'm doing wrong.

Thanks.
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