CodeMirror rego mode for syntax highlighting of rego policies

rego.js

(function(mod) {
    if (typeof exports === "object" && typeof module === "object") // CommonJS
      mod(require("../../lib/codemirror"));
    else if (typeof define === "function" && define.amd) // AMD
      define(["../../lib/codemirror"], mod);
    else // Plain browser env
      mod(CodeMirror);
})(function(CodeMirror) {

function wordRegexp(words) {
  return new RegExp("^((" + words.join(")|(") + "))\\b");
}

var keywordsList = ["default", "not", "package", "import", "as", "with", "else", "some"];
var constantsList = ["true", "false", "null"];

var keywords = wordRegexp(keywordsList);
var constants = wordRegexp(constantsList);

CodeMirror.registerHelper("hintWords", "rego", keywordsList.concat(constantsList));

CodeMirror.defineMode("rego", function(config) {
  return {
    token: function(stream, state) {
      if (stream.eatSpace()) return null;
      if (stream.match(/^#.*/)) return "comment";
      if (stream.match(/[{}\[\]\(\)]/)) return "bracket";
      if (stream.match(keywords)) return "keyword";
      if (stream.match(constants)) return "atom";
      if (stream.match(/[\=|\!\=|>|<|<\=|>\=|\+|-|\*|%|/|\||&|:\=]/)) return "operator";
      if (stream.match(/[\.,]/)) return "punctuation";
      if (stream.match(/\b[a-zA-Z_]+[a-zA-Z0-9_]*/)) return "variable";
      if (stream.match(/(-?(0|[1-9]\d*(\.\d+)?([eE][+-]?\d+)?))/)) return "number";
      if (stream.match(/"(\\["/bfnrt]|u[0-9a-fA-F]{4})*?[^"]*"/)) return "string";

      var ch = stream.next();

      return "error";
    },
    closeBrackets: "()[]{}''\"\"``",
    lineComment: "#"
  };

});

CodeMirror.defineMIME("text/x-rego", "rego");

});