mixn

Useful functinos for redux reducers. Allows easy extension of redux reducer functions. Tries each one until the state changes. No dependencies.

Usage

mixn

Mixes reducers in order. The resulting reducer function will try all available reducers until a new state is obtained, thus it is recommended to keep the state object immutable.

const { mixn } = require('mixn')

function reduce1 (state = 0, action) {
  switch (action && action.type) {
    case 'ADD':
      return state + action.payload
    case 'SUBTRACT':
      return state - action.payload
    default:
      return state
  }
}

function reduce2 (state = reduce1(), action) {
  switch (action && action.type) {
    case 'MULTIPLY':
      return state * action.payload
    default:
      return state
  }
}

function reduce3 (state = reduce1(), action) {
  switch (action && action.type) {
    case 'ADD':
      return state + action.payload * 2
    case 'DIVIDE':
      return state / action.payload
    default:
      return state
  }
}

const reduce = mixn([
  reduce1,
  reduce2,
  reduce3
])

reduce(10, { type: 'MULTIPLY', payload: 11 })
// 110

muxn

Muxes all handler objects and creates a reducer function. A handler object is a dictionary, which contains action.type as key and a reducer function(state, action) * as value. If two handlers each contain a reducer for a specific action, the last one in order takes precedence.

const { muxn } = require('mixn')
const reduce = muxn({
  ADD: (state, action) => state + action.payload
  SUBTRACT: (state, action) => state - action.payload
}, {
  DIVIDE: (state, action) => state / action.payload
})
reduce(10, { type: 'DIVIDE', payload: 2 })
// 5

withDefaultState

Wraps a reducer and sets a default state if it is undefined.

const { muxn, withDefaultState } = require('mixn')
const handler = {
  ADD: (state, action) => state + action.payload
}
const reduce = withDefaultState(10)(muxn(handler))
reduce()
// 10

License

MIT

Copyright 2017 Jerko Steiner