allow use self with globs

[mdinger]

Importing all the subnames of a module is easily done with globs but if you also want to import the module, then you need 2 separate lines to do so:

use my_mod::*;
use my_mod;

Without globs it's not an issues:

use my_mod::{self, foo, bar, baz};

It would be convenient to allow globs to import the module on the same line as well. Here are some possible syntaxes which (I think) could be understandable:

use my_mod::{self, *};
use my_mod::+;

+ is mainly because * and + are common with globs. + typically means one or more while * is any number of elements so they aren't exactly similar but it doesn't seem too unusual.

[Kimundi]

I think that this use case is obscure enough that enabling a composition like use my_mod::{self, *}; is the far better alternative than new syntax, if it should be allowed at all.

[codyps]

I like use my_mod::{self, *} too.

[mdinger]

@Kimundi That's pretty fair. It could always be added later too if it was really desired which I'm not certain it is.

[withoutboats]

I think {self, *} should definitely be possible, but this seems like a really uncommon case. Why would you want to import the module AND everything in the module?

[mdinger]

@withoutboats Eh, I think I've done it before but I can't find any. Anyway, maybe you're writing lots of tests and you use globs for convenience for importing types but your preference is to call functions through the module (maybe functions didn't used to be importable through use but now they can...). Maybe it's quick and dirty when you've got {self, A, B, C, D, E} and things are being shuffled so you just up and replace it with {self, *}. Then fix it later.

[withoutboats]

A case where this would be useful would be enabling enum imports:

use std::option::Option::{self, *};.