text: lucid.html.bootstrap.traits.Modifiable = {
  
      traitInit:function() {
          this.requireProperties('Modifiable', ['bootstrapModifiersAllowed', 'bootstrapModifierPrefix']);
      },
  
      setModifier:function(val) {
          if (this.bootstrapModifiersAllowed.indexOf(val) < 0) {
              throw new lucid.html.exception.InvalidAttributeValue(this.instantiatorName, 'modifier', val, this.bootstrapModifiersAllowed);
          }
  
          var classesToRemove = [];
          for (var i=0; i<this.bootstrapModifiersAllowed.length; i++) {
              classesToRemove.push(this.bootstrapModifierPrefix + '-' + this.bootstrapModifiersAllowed[i]);
          }
          this.removeClass(classesToRemove);
          
          if (val === null) {
              return this;
          } else {
              this.addClass(this.bootstrapModifierPrefix+'-'+val);
              return this;
          }
      }
  };
  