counter.js 389 B

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  1. import { ADD, MINUS } from '../constants/counter'
  2. const INITIAL_STATE = {
  3. num: 0
  4. }
  5. export default function counter (state = INITIAL_STATE, action) {
  6. switch (action.type) {
  7. case ADD:
  8. return {
  9. ...state,
  10. num: state.num + 1
  11. }
  12. case MINUS:
  13. return {
  14. ...state,
  15. num: state.num - 1
  16. }
  17. default:
  18. return state
  19. }
  20. }