Reselect Redux 函数返回的 TypeScript 类型？

Question

是否可以在Redux的Reselect中定义createSelector函数的返回类型？

我无法从官方文档中弄清楚这一点:https://github.com/reduxjs/reselect#q-are-there-typescript-typings

这个备忘单似乎也没有提供这一点: https://github.com/piotrwitek/react-redux-typescript-guide#selectors-with-reselect

import { createSelector } from 'reselect';

import { TodosState } from './reducer';

export const getTodos = (state: TodosState) => state.todos;

export const getTodosFilter = (state: TodosState) => state.todosFilter;

export const getFilteredTodos = createSelector(getTodos, getTodosFilter, (todos, todosFilter) => {
  switch (todosFilter) {
    case 'completed':
      return todos.filter(t => t.completed);
    case 'active':
      return todos.filter(t => !t.completed);

    default:
      return todos;
  }
});

如果我知道 getFilteredTodos 的返回结果是这样的:

type Return = {
  text: string;
  completed: boolean;
}[]

那我可以定义这个吗？

Answer 1

您可以像这样定义返回:

export const getFilteredTodos = createSelector(getTodos, getTodosFilter, (todos, todosFilter) : { text: string; completed: boolean; }[] => {
  switch (todosFilter) {
    case 'completed':
      return todos.filter(t => t.completed);
    case 'active':
      return todos.filter(t => !t.completed);

    default:
      return todos;
  }
});