docs: function parseOption(nest, cons, name) {
      if(name in options) {
        var opt = options[name]
        var prev = this[name]
        var next
        if(nest ? (Array.isArray(opt) && Array.isArray(opt[0])) :
                   Array.isArray(opt) ) {
          this[name] = next = [ cons(opt[0]), cons(opt[1]), cons(opt[2]) ]
        } else {
          this[name] = next = [ cons(opt), cons(opt), cons(opt) ]
        }
        for(var i=0; i<3; ++i) {
          if(next[i] !== prev[i]) {
            return true
          }
        }
      }
      return false
    }