HLASM Language Reference

&SYSNEST System Variable Symbol
Statement 7 is the 106th macro instruction processed. Therefore, &SYSNDX is
assigned the number 0106 for that macro instruction. The number 0106 is
substituted for &SYSNDX when it is used in statements 4 and 6. Statement 4 is
used to assign the character value 16 to the SETC symbol &NDXNUM Statement 6
is used to create the unique name B16.
Statement 5 is the 107th macro instruction processed. Therefore, &SYSNDX is
assigned the number 17 for that macro instruction. The number 17 is
substituted for &SYSNDX when it is used in statements 1 and 3. The number 16
is substituted for the global-scope SETC symbol &NDXNUM in statement 2.
Statement 8 is the 108th macro instruction processed. Therefore, each occurrence
of &SYSNDX is replaced by the number 18. For example, statement 6 is used to
create the unique name B18.
When statement 5 is used to process the 108th macro instruction, statement 5
becomes the 109th macro instruction processed. Therefore, each occurrence of
&SYSNDX is replaced by the number 19. For example, statement 1 is used to
create the unique name A19.
&SYSNEST System Variable Symbol
Use &SYSNEST to obtain the current macro instruction nesting level.
The local-scope system variable symbol &SYSNEST is assigned a read-only value
each time a macro definition is called from a source module.
The value assigned to &SYSNEST is a number from 1 to 99999999. No leading
zeros are generated as part of the number. When a macro is called from open
code, the value assigned to &SYSNEST is the number 1. Each time a macro
definition is called by an inner macro instruction, the value assigned to &SYSNEXT
is incremented by 1. Each time an inner macro exits, the value is decremented by
1.
Notes:
1. The value of the type attribute of &SYSNEST (T'&SYSNEST) is always N.
2. The value of the count attribute (K'&SYSNEST) is equal to the number of digits
assigned.
The following example shows the values assigned to &SYSNEST:
Chapter 7. How to Specify Macro Definitions 283