export class Helper { returns public static guid = ( ) : string => { return Helper . s4 ( ) + Helper . s4 ( ) + '-' + Helper . s4 ( ) + '-' + Helper . s4 ( ) + '-' + Helper . s4 ( ) + '-' + Helper . s4 ( ) + Helper . s4 ( ) + Helper . s4 ( ) ; } ; returns private static s4 ( ) { return Math . floor ( ( 1 + Math . random ( ) ) * 0x10000 ) . toString ( 16 ) . substring ( 1 ) ; } }