Not possible to use language injection on regexes

[hugopl]

There's a regex tree-sitter grammar and some other grammar uses it to highlight regular expressions using the tree-sitter injection mechanism.

e.g.: The ruby injection.scm for regexes looks like

(regex
  (string_content) @injection.content
  (#set! injection.language "regex"))

So editors delegate the regex contents highlighting to another parser.

This is not possible yet on Crystal parser because there's just a single regex node that includes the regex delimiters.

[keidax]

It would be nice to offload the regex syntax details to another grammar. Not entirely clear to me if tree-sitter-regex supports the same set of regex syntax as Crystal: tree-sitter/tree-sitter-regex#41