ios - Making a single copy of a singleton -

a design question:

i have singleton (in objective-c doesn't matter)

the singleton class (object) data structure many classes access, , single (hence - singleton)

now want add ability undo - saving snapshot of state of object - can go it.

what need break singleton-ness of object (need 1 copy of it). not allow me share conveniently between classes.

ideas?

"the singleton class (object) data structure many classes access, , single"

i think easier make singleton object have collection of data structure. create copies of data structure instead of copies of singleton.