HLASM Language Reference

Levels of Macro Call Nesting
When the assembler processes a macro exit instruction, either MEXIT or MEND, it
selects the next statement to process depending on the level of nesting. If the
macro exit instruction is from an inner macro, the assembler processes the next
statement after the statement that called the outer macro. The next statement in
open code might come from the AINSERT buffer. If the macro exit instruction is
from an outer macro, the assembler processes the next statement in open code,
after the statement that called the inner macro.
Passing Values through Nesting Levels
The value contained in an outer macro instruction operand can be passed through
one or more levels of nesting (see Figure 85 on page 315). However, the value
specified (see ▌1▐ in Figure 85) in the inner macro instruction operand must be
identical to the corresponding symbolic parameter (see ▌2▐ in Figure 85) declared
in the prototype of the containing macro definition.
Thus, a sublist can be passed (see ▌3▐ in Figure 85) and referred to (see ▌4▐ in
Figure 85) as a sublist in the macro definition called by the inner macro call. Also,
any symbol (see ▌5▐ in Figure 85) that is passed carries its attribute values through
the nesting levels.
If inner macro calls at each level are specified with symbolic parameters as
operand values, values can be passed from open code through several levels of
macro nesting.
COMPAT(SYSLIST) Assembler Option: If the COMPAT(SYSLIST) assembler
option is specified, and a symbolic parameter is only a part of the value specified in
an inner macro instruction operand, only the character string value given to the
parameter by an outer call is passed through the nesting level. Inner sublist entries
are, therefore, not available for reference in the inner macro.
314 HLASM V1R5 Language Reference