Misago/frontend/src/reducers/participants.js

export const REPLACE_PARTICIPANTS = 'REPLACE_PARTICIPANTS';

export function replace(newState) {
  return {
    type: REPLACE_PARTICIPANTS,
    state: newState
  };
}

export default function participants(state=[], action=null) {
  switch (action.type) {
    case REPLACE_PARTICIPANTS:
      return action.state;

    default:
      return state;
  }
}