import toDate from '../toDate/index' ; import requiredArgs from '../_lib/requiredArgs/index' ; name category summary description param { Date | Number } date returns { Number } throws example export default function getISODay ( dirtyDate ) { requiredArgs ( 1 , arguments ) ; const date = toDate ( dirtyDate ) ; let day = date . getDay ( ) ; if ( day === 0 ) { day = 7 ; } return day ; }