Syntax - Match word based on a previous match

Question

I want to highlight all words that have been matched in another syntax region. Using something similar to regex capture groups, for example given a file:

{highlightme} asda asasd asd asd as hightlightme asd adsasd asd
asdaskj highlightme weqeqw (highlightme) {highlightme}

I want to be able to highlight all highlightme IF any one of the highlightme is surrounded with curly braces. What I have so far:

syntax region testSurr start=/{/ end=/}/ contains=testKey nextgroup=testAfter
syntax match testKey /\v\w+/ contained
syntax region testAfter start=/\v\_.*/ end=/\v\_.*/ contained contains=testKey

This works. It highlights all instances of a word if that word is ever matched in a curly brace. However, it also clears the highlighting of everything else in the file. How can I achieve the same result, but preserve the highlighting of everything else?

Answer 1

late answer but might still be useful for you or others.

You could do:

syn region testregion start='{' end='}' contains=testhi
syn keyword testhi highlightme contained

hi def testhi cterm=italic,bold 

and just don't define a highlighting for the region. Might even add more keywords.