https://github.com/maxhallinan/redeuceur

A utility for creating terse Redux reducers.
https://github.com/maxhallinan/redeuceur

redux redux-reducers

Last synced: about 1 month ago
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A utility for creating terse Redux reducers.

• Host: GitHub
• URL: https://github.com/maxhallinan/redeuceur
• Owner: maxhallinan
• License: mit
• Created: 2017-06-29T22:03:44.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2017-09-14T08:33:51.000Z (over 7 years ago)
• Last Synced: 2024-11-07T06:09:21.351Z (about 2 months ago)
• Topics: redux, redux-reducers
• Language: JavaScript
• Homepage:
• Size: 56.6 KB
• Stars: 10
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: readme.md
  • License: license

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README

        
# redeuceur

[![Build Status](https://travis-ci.org/maxhallinan/redeuceur.svg?branch=master)](https://travis-ci.org/maxhallinan/redeuceur)

[![Coverage Status](https://coveralls.io/repos/github/maxhallinan/redeuceur/badge.svg?branch=master)](https://coveralls.io/github/maxhallinan/redeuceur?branch=master)

A utility for creating terse Redux reducers. 

## Install

```bash

$ npm install --save redeuceur

```

## Usage

```javascript

import redeuceur from 'redeuceur';

const initialState = {};

const handlers = [

  [

    // handle a single action type

    ActionTypes.CREATE_FOO,

    // return the next state

    (state, action) => action.foo,

  ],

  [

    // handle one of many action types

    [ ActionTypes.DELETE_FOO, ActionTypes.RESET_FOO, ],

    // return a static value

    {},

  ],

  [

    // handle an arbitrary condition

    (state, action) => action.type === ActionTypes.UPDATE_FOO && !state.isBar,

    // return a computed value

    (state, action) => Object.assign({}, state, action.foo),

  ],

];

const foo = redeuceur(initialState, ...handlers);

```

## API

### redeuceur(initialState, handler[,...])

Takes an initial state value and one or more handlers, and returns a Redux reducer.

#### initialState

Type: `state`

The reducer is initialized to the value of `initialState`.

#### handler

Type: `Array`

Every handler is a `[condition, nextState]` pair. A handler specifies when to change

state (`condition`) and what change to make (`nextState`). 

If no conditions are met, the reducer returns the last state. Thus, the default 

case is handled implicitly.

Handlers are evaluated in the order they are provided to `redeuceur`. The reducer

returns the `nextState` value of the first match.

##### condition

Type: `String`, `Array String`, `(state, action) -> Boolean`

A string condition is met when the string strictly equals the action type.

An array condition is met when one string strictly equals the action type.

A function condition is met when `condition(state, action)` returns a truthy value.

##### nextState

Type: `(state, action) -> state`, `state`

If `nextState` is a function, the result of `nextState(state, action)` is 

returned as the next state. Otherwise, the value of `nextState` is returned.

## License

MIT © [Max Hallinan](https://github.com/maxhallinan)