Re: xref "find references" and grouping

[Dmitry Gutov]

On 05/03/2015 10:47 AM, Helmut Eller wrote:

> Not sure what you mean.  Trees can be ordered and a list of tree-paths
> would seem enough to describe an ordered tree.

Ok, you're right. There's nothing impossible in a comparison function 
accepting lists of different lengths.

I can offer another, recently surfaced critique: if all groups are 
simply strings, we can't do content-specific things to them at display. 
For instance, can't shorten file paths.

Tree widgets can have specialized subclasses.

> Sounds like there would not be much left to be shared between different
> languages.

That's a very surprising conclusion. What prompted it? Like you said, 
we're not sorting now anyway. There's not much language-specific in the 
proposal.

A set of widgets (like generic group, file group, method group, and a 
few kinds of locations) will allow any language mode to return a 
structured set of matches, which can even be rendered in different ways.

> Maybe we should never have tried to generalize this anyway
> and simply declare a convention that programming modes should bind
> M-. to a find-definition-like command.  That certainly would avoid the
> current dilemma of pleasing everybody.

By allowing every mode to behave in its own way? That would certainly 
please every user.

> A rename feature would probably benefit from an UI that's
> separate/independent from find-definition.

It would be different, but not necessarily vastly different. And the set 
of returned xrefs we're getting from the "find references" command is 
already enough to base a simplistic rename on.