Function quote

src/util/stringify.js:63–78

(string)

function quote(string) {

  // If the string contains no control characters, no quote characters, and no
  // backslash characters, then we can safely slap some quotes around it.
  // Otherwise we must also replace the offending characters with safe escape
  // sequences.

  escapable.lastIndex = 0;
  return escapable.test(string) ? '"' + string.replace(escapable, function (a) {
    var c = meta[a];
    return typeof c === 'string'
      ? c
      : '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
  }) + '"' : '"' + string + '"';

}

function str(key, holder) {