Syntax improvements for defs and symbols

[tonsky]

Description of the Change

In top-level definitions like

(defn f [] (+ 1 2))

we shouldn’t mark the whole expression as "meta.definition.global.clojure". Instead, we should mark only f (function name) as "entity.name.global.clojure meta.definition.global.clojure". This is similar to how other syntaxes do it, e.g. JavaScript and Python.

In addition to that, this PR contains a couple of fixes to existing regexps:

• Recognize single-char symbols
• Symbols can’t start with [0-9#']
• Symbols can contain [#$%&'|]
• When defining dynamic var (def *var* ...), capture *var* as "entity.name.global" as well

Alternate Designs

Not applicable

Benefits

• Better syntax highlighting
• Syntax highlighting working closer to other languages

Possible Drawbacks

Existing themes that were designed specifically with Clojure syntax in mind might break (I doubt ones exist, though)

Applicable Issues

Not applicable

---

This change is 

[tonsky]

Agree. Looks like in other languages meta.definition tends to capture the whole expression, while entity.name is usually just class/function name. I made the appropriate changes. I also think entity.name.definition.clojure is a better name than entity.name.global.clojure because meta is called meta.defintion.global.clojure, with definition being the main semantic part and global just a modifier

[50Wliu]

I don't think that patterns: include $self block should actually be there. Since before it was at the wrong indentation and not doing anything and similar grammars don't have it.

[tonsky]

Actually, I think I messed up the indentation when I copied it back. 'patterns' was on the same level as 'captures' and I accidentally made it deeper. Would it make more sense if I return it the way it was before?

[50Wliu]

@tonsky the previous indentation, with the patterns at the same level as captures, also doesn't make sense. That syntax is only for begin/end patterns and not regular matches.