VIM syntax highlighting of html nested in yaml

Question

Given a yaml file that contains html, like this:

template        : |+ 
    
Hello, world

Is

Answer 1

check out my related question: Trouble using Vim's syn-include and syn-region to embed syntax highlighting. There I am trying to embed Python within TeX, but I think the solution might work for your case, too.

I think you want to do something like this:

let b:current_syntax = ''
unlet b:current_syntax
runtime! syntax/yaml.vim

let b:current_syntax = ''
unlet b:current_syntax
syntax include @YaML syntax/yaml.vim

let b:current_syntax = ''
unlet b:current_syntax
syntax include @HTML syntax/html.vim
syntax region htmlEmbedded matchgroup=Snip start='#{{{html' end='#html}}}' containedin=@YaML contains=@HTML

hi link Snip SpecialComment
let b:current_syntax = 'yaml.html'

The block with the runtime! command might be unnecessary if your YaML is already highlighted.