On 10/15/15 10:31 AM, Jonathan M Davis wrote:
On Thursday, 15 October 2015 at 14:13:34 UTC, Steven Schveighoffer wrote:
Nobody else finds this to be an issue? Should we just close bugs like
15179 with "sorry, please import everything you need local or global,
too bad the phobos/druntime changes broke your code"?
It's an issue, but I confess that I kind of gave up on local imports
working correctly when they refused to make UFCS work with local imports
Huh? UFCS works with local imports.
void main()
{
import std.conv: to;
import std.stdio: writeln;
1.to!string.writeln; // works
}
(though IIRC, that was specifically Kenji and not Walter - I don't know
where Walter sits on it). I really don't think that local imports should
be any different from imports at the module level except for the fact
that they don't affect stuff at outer scopes, but I gather that the
implementation doesn't jive well with that, and that's led to refusals
to make imports work the same at all levels when various issues like
this have come up.
Do you have links to these refusals? I didn't know this was considered
and rejected.
That being said, D's module system does tend to have issues when adding
symbols to druntime, Phobos, or any library that someone else might use.
So, on some level, we're always going to have this problem, but we can
and should do better with that then we do (e.g. making it so that
private symbols never conflict with anything when the module that
they're in is imported).
Any time we duplicate any symbol name between 2 modules, we can cause
regressions. If we don't fix this, either we never name any symbol the
same thing in 2 modules, or we simply close as invalid any bug that
depends on using local vs. global imports.
I'm OK with the latter, the former is likely impossible. But some
official position should be taken here.
And the requirement to import the module you are currently in, just
smells. A lot.
-Steve
