npm install hard-reducer --save# oryarn add hard-reducer

Concepts

Examples

/*@flow */// ^ flow magic comment to activate. It will be ignored in typescript.import{buildActionCreator,createReducer,typeActionCreator}from"hard-reducer";// ^ If you use typescript, Do not use `type` before ActionCreatorconst{ createAction}=buildActionCreator({prefix:"counter/"});// Add type to your payload by ActionCreatorconstinc:ActionCreator<number> = createAction("inc");// or infer by function resultconst dec = createAction("dec", (val: number) =>val);inc(1);//=> { type: 'counter/inc', payload: 1 }// Define state typetypeState={value:number};constinitialState:State={value:0};constreducer=createReducer(initialState)// Handle `(State, Payload) => State` in matched context..case(inc,(state,payload)=>{return{value:state.value+payload};}).case(dec,(state,payload)=>{// $ExpectErrorconstp:string=payload;return{value:state.value-payload};})// Take string.case("other/noop",(state,payload)=>{returnstate;})// Take all uncaught action, not payload!.else((state,action)=>{console.log("default fallback");returnstate;});// Use itconstret0=reducer(initialState,inc(3));constret1=reducer(ret1,dec(1));

Handle async action: createAsyncAction

/*@flow */import{createReducer,buildActionCreator}from"hard-reducer";const{ createAsyncAction}=buildActionCreator();constincAsync=createAsyncAction("inc-async",async(val:number)=>{if(val%2===1){thrownewError("error");}return{p:1};});typeStatus="ready"|"started"|"resolved"|"rejected";typeState={status:Status,payload: ?{p:number}};constreducer=createReducer({status:"ready",payload:null}).case(incAsync.started,state=>{return{state:"started"};}).case(incAsync.resolved,(state,payload)=>{return{state:"resolve", payload};}).case(incAsync.rejected,(state,error)=>{return{state:"ready",payload:null};});// storeimportreduxThunkfrom"redux-thunk";import{applyMiddleware,createStore}from"redux";conststore=createStore(reducer,undefined,applyMiddleware(reduxThunk));store.subscribe((...args)=>{console.log("store",store.getState());});// dispatchstore.dispatch(incAsync(1));

Handle thunk action: createThunkAction

import{createReducer,buildActionCreator}from"hard-reducer";const{ createThunkAction, createAction}=buildActionCreator();constinc=createAction("inc",(val:number)=>val);constthunked=createThunkAction("thunked",async(input,dispatch,getState)=>{dispatch(inc(input.value));return{ret:true};});// HandlecreateReducer({status:"ready",payload:null}).case(thunked.started,state=>{return{state:"started",payload:null};}).case(thunked.resolved,(state,payload)=>{return{state:"resolve", payload};}).case(thunked.rejected,(state,error)=>{return{state:"ready",payload:null};});// dispatchstore.dispatch(thunked({value:1}));

Related projects

ChangeLog

LICENSE