Is there any reason to allow 'import name;'

[marijnh]

Where name is a single identifier without module path.

If the import can see it, it was already visible, so importing doesn't help. Thus, we can simply ignore such directives. Or we can disallow them for being bogus.

Thoughts?

[brson]

The only effect I can think of is that it verifies that some identifier is in scope, so you could

``
import std::vec::*;
import filter_map;

To protect yourself against filter_map disappearing from the vec mod. Not particularly useful. I agree it could be made an error.

[marijnh]

It looked as if my solution for #1114 would interact badly with this, but in fact it doesn't, so I'm in favour of just leaving it in for consistency. (import foo = bar; should definitely be allowed).