ARM VERSION 1.2 manual Macro and Mend

Directives Reference

7.4.2MACRO and MEND

The MACRO directive marks the start of the definition of a macro. Macro expansion terminates at the MEND directive. See Using macros on page 2-48 for further information.

Syntax

Two directives are used to define a macro. The syntax is:

MACRO

{$label} macroname {$parameter{,$parameter}...}

;code

MEND

where:

$label

	is a parameter that is substituted with a symbol given when the
	macro is invoked. The symbol is usually a label.
macroname	is the name of the macro. It must not begin with an instruction or
	directive name.
$parameter
	is a parameter that is substituted when the macro is invoked. A
	default value for a parameter can be set using this format:
	$parameter="default value"
	Double quotes must be used if there are any spaces within, or at
	either end of, the default value.

Usage

If you start any WHILE...WEND loops or IF...ENDIF conditions within a macro, they must be closed before the MEND directive is reached. See MEXIT on page 7-29 if you need to allow an early exit from a macro, for example from within a loop.

Within the macro body, parameters such as $label, $parameter can be used in the same way as other variables (see Assembly time substitution of variables on page 3-14). They are given new values each time the macro is invoked. Parameters must begin with $ to distinguish them from ordinary symbols. Any number of parameters can be used.

$label is optional. It is useful if the macro defines internal labels. It is treated as a parameter to the macro. It does not necessarily represent the first instruction in the macro expansion. The macro defines the locations of any labels.

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