wrapReducers.md

API Reference for wrapReducers

• Methods
  • wrapReducers
  • wrapActions

Methods

wrapReducers

wrapReducers(
  nestedReducers,
  options = defaultOptions
)

wrap a reducer from an object with {action.type: function} or {action.type: {action.status: function}}, therefore renders would render state change wisely by the accepted action.type and action.status.

wrapReducers({type: function})

wrapReducer creates Redux reducer by action.type;

Example

The following code block

let reducer = wrapReducers({
  add: (state, action) => {count: state.count + action.count},
  sub: (state, action) => {count: state.count - action.count},
  })

is an equivalence to

let reducer = function (state, action) {
  switch(action.type) {
    case 'add':
      return {...state, count: state.count+ action.count};
      break;
    case 'sub':
      return {...state, count: state.count- action.count};
      break;
    default:
      return state;
  }
}

wrapRedcers({type: {status: function}})

wrapReducers creates Redux reducers by action.type and by action.status, and wrapReducers automatically merges reducer rules with and without action.status.

Example

The following code block

let reducer = wrapReducers({
  add: (state, action) => {count: state.count + action.count},
  sub: {
    success: (state, action) => {count: state.count- action.count};
    error: (state, action) => {count: 999}
  }
  })

is an equivalence to

let reducer = function (state, action) {
  switch(action.type) {
    case 'add':
      return {...state, count: state.count+ action.count};
      break;
    case 'sub':
      switch (action.status) {
        case 'success': 
          return {...state, count: state.count - action:count};
        case 'error': 
          return {...state, count: 999};
        default:
          return state;
      }
      break;
    default:
      return state;
  }
}

wrapReducers(nestedReducers, options)

Some addtional configuration is provided by options.

1. options.statusKey, by default 'status' This option determines where to search the status in the dispatched action.
   If we set options.statusKey = 'cat', in all example above, the action.status will be replaced by action.cat.

2. options.defaultState, by default {} This option determines the default Redux State set by the reducer;

3. options.autoFixState, by default true This options determines whether reducers would add {...state} in the state change. If false, all ...state in the exmaples above will be deleted.