redux/arc.js
function themeReducer(state = initialState, action) {

    switch (action.type) {

        case CONSTANTS.theme.setTheme:
            return {
                ...state,
                theme: action.theme,
                navigationOptions: action.navigationOptions,
                contentOffset: action.contentOffset,
            }
        default:
            return state
    }
}
function themeReducer(state = initialState, action) {

    switch (action.type) {

        case CONSTANTS.theme.setTheme:
            return {
                ...state,
                theme: action.theme,
                navigationOptions: action.navigationOptions,
                contentOffset: action.contentOffset,
            }
        default:
            return state
    }
}
function themeReducer ( state = initialState , action ) { switch ( action . type ) { case CONSTANTS . theme . setTheme : return { ... state , theme : action . theme , navigationOptions : action . navigationOptions , contentOffset : action . contentOffset , } default : return state } }
reducer
reducer