code: function concat() {
      var observables = [];
      for (var _i = 0; _i < arguments.length; _i++) {
          observables[_i] = arguments[_i];
      }
      return function (source) { return source.lift.call(_observable_concat__WEBPACK_IMPORTED_MODULE_0__["concat"].apply(void 0, [source].concat(observables))); };
  }
docs: PURE_IMPORTS_START _observable_concat PURE_IMPORTS_END