Comment on draft PEP for deprecating six builtins

[Alex Martelli]

Martin v. Löwis wrote:
        ...
>> Right now, .PTH files handle importing and path-setting needs of
>> installed packages.  Having them handle such packages' builtins-needs
>> as well seems a minor extension.
> 
> The current .PTH design allows for that kind of operation already:
> 
> # functional_compat.py
> import __builtin__
> exec "from functional import map,filter,reduce" in __builtin__.__dict__
> 
> # functional_compat.pth
> import functional_compat
        ...
> My original intention was that those import lines in .pth files can
> install Unicode codecs in the codecs registry, but they, of course,
> all for the execution of arbitrary stuff.

Right -- "import" can indeed "execute arbitrary stuff".  So, one way
to do the "minor extension" I was musing about would be to provide
suitable modules (perhaps a package) for the typical compatibility
needs related to builtins being deprecated or moved away.  Although
it appears to me that having the PTH file accept "from x import y,z"
and implicitly execute that in __builtin__.__dict__ might be more
direct and immediate for people who write .PTH files.


Alex