Maintaining global state with m4 macros

Is it possible to create an m4 macro expanding to the next integer of
a global counter each time it's called?
In other words, assuming the counter has an initial value (e.g. 0),
these calls to such a nextcount macro:

    First call: nextcount

    Second call: nextcount

    Third call: nextcount

should generate the following output:

    First call: 1

    Second call: 2

    Third call: 3

I'm stumped as I'm not sure updating the global state of a counter is
even possible with m4. Is there any way?

Thanks,


Paolo