chapter: Grammar
  ==================
  var that = this;
      
      
  ====================================
  /*
      var rm_a = /a*/.match(s);
  */
      
      
  ====================================
  abstract
  boolean break byte
  case catch char class const continue
  debugger default delete do double
  else enum export extends
  false final finally float for function
  goto
  if implements import in instanceof int interface
  long
  native new null
  package private protected public
  return
  short static super switch synchronized
  this throw throws transient true try typeof
  var volatile void
  while with
      
      
  ====================================
  "A" === "\u0041"
      
      
  ====================================
  'c' + 'a' + 't' === 'cat'
      
      
  ====================================
  'cat'.toUpperCase(  ) === 'CAT'
      
      
  ====================================
  for (myvar in obj) {
      if (obj.hasOwnProperty(myvar)) {
          ...
      }
  }
      
      
  ====================================
  2 + 3 * 5 === 17
  (2 + 3) * 5 === 25
      
      
  ==================