Error: The slice reducer for key “Todos“ returned undefined during initialization.

Error: The slice reducer for key “Todos“ returned undefined during initialization.

在练习redux时一直进行报错，没想到竟然是这么小的问题,就离谱，大家看到了引以为戒

Uncaught Error: The slice reducer for key "Todos" returned undefined during initialization. If the state passed to the reducer is undefined, you must explicitly return the initial state. The initial state may not be undefined. If you don't want to set a value for this reducer, you can use null instead of undefined.

没改之前的代码

function Todos (state, { type, payload }){switch (type) {case 'todos/del':return {...state,//filter过滤出不相同的数据并返回list: state.list.filter((item) => item.id != payload),};default:return state;}
}
export default  Todos 

修改之后的代码

function Todos (state, { type, payload }){switch (type) {case 'todos/del':return {...state,//filter过滤出不相同的数据并返回list: state.list.filter((item) => item.id != payload),};default:return {...state};}
}
export default  Todos