I believe this is because the type for [] is inferred to be never[], which is the type for an array that MUST be empty. You can use a type cast to address this: [‘a’, ‘b’, ‘c’].reduce((accumulator, value) => accumulator.concat(value), [] as string[]); Normally this wouldn’t be much of a problem since TypeScript does a … Read more
You need to transform your todos array to have the appropriate item updated. Array.map is the simplest way to do this: case “COMPLETE_TASK”: return { …state, todos: state.todos.map(todo => todo.id === action.id ? // transform the one with a matching id { …todo, completed: action.completed } : // otherwise return original todo todo ) }; … Read more
Starting another dispatch before your reducer is finished is an anti-pattern, because the state you received at the beginning of your reducer will not be the current application state anymore when your reducer finishes. But scheduling another dispatch from within a reducer is NOT an anti-pattern. In fact, that is what the Elm language does, … Read more