Universal tag structure, was: Re: IDE

[Dmitry Gutov]

On 10/28/2015 01:39 PM, Eric Ludlam wrote:

> What is optimal?

Can't really say.

> For me, it was about pulling all the datatype
> information out of the syntax, and differentiating between different tag
> classes, and having something that was Emacs friendly, and extensible to
> any language, no matter how strange.

Sounds like a good direction.

> For me, Semantic's tag structure
> is pretty good.  It has 5 slots:
>
> * The name, as 'car' so you can use assoc and other friendly things.
> * The class of the tag is next, as all languages have different kinds of
> tags.
> * plist of attributes, extensible to use anything, but with some common
> attribute names defined for use via API.
> * plist of properties, or bits of data needed by the tooling, which is
> arbitrary and extensible for whatever a tool might need.
> * Buffer binding information - either the [start end] of the tag, or an
> overlay.

Sections 3 and 4 are a little vague, for a format description. If they 
contain important data, it should be standardized somehow.

Regarding "buffer binding information", I think that's too 
Semantic-specific. Instead, maybe a tag should be able to "find" itself 
(probably by implementing some generic function). Whether it's via 
keeping a reference to an overlay, consulting some index, or external 
process, or simply running Grep again.

> That makes the tag extensible for almost any situation, and keeps TAG
> data and OPERATIONAL data separate, saveable, and searchable.

Overlays are a part of the "operational" data, IMO.

I don't intend working on this in the near future, though, so I'd like 
to bow out of the detailed discussion of the format, for now.