function assign ( target , ... sources ) { if ( target == null ) { throw new TypeError ( 'Cannot convert undefined or null to object' ) ; } var to = Object ( target ) ; for ( var index = 0 ; index < sources . length ; index ++ ) { var nextSource = sources [ index ] ; if ( nextSource != null ) { for ( var nextKey in nextSource ) { if ( Object . prototype . hasOwnProperty . call ( nextSource , nextKey ) ) { to [ nextKey ] = nextSource [ nextKey ] ; } } } } return to ; } export { assign } ;