src/layui.js
function onCallback(){
      exports.push(layui[item]);
      apps.length > 1 ?
        that.use(apps.slice(1), callback, exports)
      : ( typeof callback === 'function' && callback.apply(layui, exports) );
    }
function onCallback(){
      exports.push(layui[item]);
      apps.length > 1 ?
        that.use(apps.slice(1), callback, exports)
      : ( typeof callback === 'function' && callback.apply(layui, exports) );
    }
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