code: function(env, language, placeholderPattern, replaceFilter) {
            if (env.language !== language) {
              return
            }
            var tokenStack = (env.tokenStack = [])
            env.code = env.code.replace(placeholderPattern, function(match) {
              if (typeof replaceFilter === 'function' && !replaceFilter(match)) {
                return match
              }
              var i = tokenStack.length
              var placeholder
              // Check for existing strings
              while (
                env.code.indexOf((placeholder = getPlaceholder(language, i))) !==
                -1
              )
                ++i
              // Create a sparse array
              tokenStack[i] = match
              return placeholder
            })
            // Switch the grammar to markup
            env.grammar = Prism.languages.markup
          }
docs: Tokenize all inline templating expressions matching `placeholderPattern`.
  
  If `replaceFilter` is provided, only matches of `placeholderPattern` for which `replaceFilter` returns
  `true` will be replaced.
  
  @param {object} env The environment of the `before-tokenize` hook.
  @param {string} language The language id.
  @param {RegExp} placeholderPattern The matches of this pattern will be replaced by placeholders.
  @param {(match: string) => boolean} [replaceFilter]