C166/ST10 Cross-Assembler, Linker/Locator, Utilities ... - Tasking

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MACRO PREPROCESSOR
2.5.3 LOCAL SYMBOLS IN MACROS
Chapter 2
As mentioned in the note to Example 3, a macro using a fixed label can
only be called once, since a second call to the macro causes a conflict in
the label definitions at assembly time. The label can be made a parameter
and a different symbol name can be specified each time the macro is
called.
A preferable way to ensure a unique label for each macro call is to put the
label in a local−list. The local−list construct allows you to use macro
identifiers to specify assembly−time symbols. Each use of a LOCAL symbol
in a macro guarantees that the symbol will be replaced by a unique
assembly−time symbol each time the symbol is called.
The macro preprocessor increments a counter once for each symbol used
in the list every time your program calls a macro that uses the LOCAL
construct. Symbols in the local−list, when used in the macro−body, receive
a three digit suffix that is the decimal value of the counter preceded by ’_’.
The first time you call a macro that uses the LOCAL construct the suffix is
’_001’.
The syntax for the LOCAL construct in the DEFINE function is shown
below. (This is the complete syntax for the built−in function DEFINE):
Syntax:
@[*]DEFINE macro−name [(parameter−list)] [@LOCAL(local−list)]
macro−body
@ENDD
The local−list is a list of valid macro identifiers separated by commas.
Since these macro identifiers are not parameters, the LOCAL construct in a
macro has no effect on a macro call.