From: "John Gilmore" <[email protected]> Sent: Monday, 16 April 2012 6:51 AM
If N - 1 is the number of macro instructions already expanded, then N, suitably padded with zero characters on the left, is the value of &SYSNDX within the current, Nth, macro expansion. Expansions may of course be nested within each other, and each expansion of any macro increments the value of &SYSNDX.
True, but when the nested call terminates, the value of &SYSNDX reverts to the value that was in effect just before the call, and remains so until the completion of that (outer) macro expansion. Then the updated value of &SYSNDX is used for the next (if any) macro call.
