export enum VALUES {
  VALUE1 = 0x0001,
  VALUE2 = 0x0002,
  VALUE3 = 0x0004,
  VALUE4 = 0x0008,
  VALUE5 = 0x0010,
  VALUE6 = 0x0020,
  VALUE7 = 0x0040,
  VALUE8 = 0x0080,
  VALUE9 = 0x0100
}

In JS it's easy to know if a mask contains a value with the & operator:

(mask & VALUES.VALUE1) === VALUES.VALUE1

But how can i compare two masks and know which are the differences or how many differences there is ?