code: function processKeywords() {
      var nodes = []
      var lastIndex
      var keyword
      var node
      var submatch
  
      if (!top.keywords) {
        return addText(modeBuffer, nodes)
      }
  
      lastIndex = 0
  
      top.lexemesRe.lastIndex = 0
  
      keyword = top.lexemesRe.exec(modeBuffer)
  
      while (keyword) {
        addText(modeBuffer.substring(lastIndex, keyword.index), nodes)
  
        submatch = keywordMatch(top, keyword)
  
        if (submatch) {
          relevance += submatch[1]
  
          node = build(submatch[0], [])
  
          nodes.push(node)
  
          addText(keyword[0], node.children)
        } else {
          addText(keyword[0], nodes)
        }
  
        lastIndex = top.lexemesRe.lastIndex
        keyword = top.lexemesRe.exec(modeBuffer)
      }
  
      addText(modeBuffer.substr(lastIndex), nodes)
  
      return nodes
    }
docs: Process keywords. Returns nodes.