Redux: TypeError: _dispatch is not a function

Created on 20 Apr 2016 · 6Comments · Source: reduxjs/redux

Here's the error:

[1] TypeError: _dispatch is not a function
[1]     at Object.dispatch (/Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/redux/lib/applyMiddleware.js:45:18)
[1]     at /Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/react-router-redux/lib/index.js:90:13
[1]     at /Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/history/lib/useQueries.js:109:9
[1]     at /Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/history/lib/useBasename.js:84:9
[1]     at Object.listen (/Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/history/lib/createHistory.js:104:7)
[1]     at Object.listen (/Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/history/lib/useBasename.js:83:22)
[1]     at Object.listen (/Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/history/lib/useQueries.js:108:22)
[1]     at middleware (/Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/react-router-redux/lib/index.js:83:34)
[1]     at /Users/thomas/Desktop/react-redux-universal-hot-example/node_modules/redux/lib/applyMiddleware.js:49:16
[1]     at Array.map (native)

Seems that a default value was removed in a commit (https://github.com/reactjs/redux/commit/9496fd793bac83cedb643aba8da2c164aaf52a15) 11 days ago.

This line here needs access to dispatch and it's undefined.

Here's how to recreate the error:

git clone https://github.com/erikras/react-redux-universal-hot-example.git
cd react-redux-universal-hot-example
npm install
npm run dev

Source

reggi

👍4

Most helpful comment

Thank you very much for reporting! Fixed in 3.5.1.

gaearon on 20 Apr 2016

👍4

All 6 comments

To get around this for now until it is fixed, you will want to use v3.4.0 instead of v3.5.0.

calvinnwq on 20 Apr 2016

The problem is react-router-redux, update version to 4.0.2 and edit your code

simonelp on 20 Apr 2016

Updating react-router-redux didn't solve it for me. I had to revert back to 3.4.0 to get my app working.

I think there is something weird in this file:
https://github.com/reactjs/redux/blob/v3.5.0/src/applyMiddleware.js#L27

In version 3.5.0 it was changed so that line 27 can potentially call empty variable set on line 22. Even if this is intentional, it looks kinda weird to me.

This is how the file looks like after babel conversion:

function applyMiddleware() {
  for (var _len = arguments.length, middlewares = Array(_len), _key = 0; _key < _len; _key++) {
    middlewares[_key] = arguments[_key];
  }

  return function (createStore) {
    return function (reducer, initialState, enhancer) {
      var store = createStore(reducer, initialState, enhancer);
      var _dispatch;
      var chain = [];

      var middlewareAPI = {
        getState: store.getState,
        dispatch: function dispatch(action) {
          return _dispatch(action);
        }
      };
      chain = middlewares.map(function (middleware) {
        return middleware(middlewareAPI);
      });
      _dispatch = _compose2["default"].apply(undefined, chain)(store.dispatch);

      return _extends({}, store, {
        dispatch: _dispatch
      });
    };
  };
}