code: function(value, result) {
      var target = result || this[0];
      var k = this.keyName(target.path);
  
      if(k && target) {
          var prev = target.value;
          target.value = value;
          var p = this.parent(target);
          if(p) {
            p.set(k, value);
          }
          else {
            this.resultModified(target, prev);
          }
      }
      return this;
    }
docs: SpahQL#replace(value) -> SpahQL
  - value (Object): The value to replace this query result's value.
  
  Replaces the value of the first item in this set, modifying the queried data
  in the process. If the first item in this set is the root, no action will be taken.
  
  Returns self.