#-------------------------------------------------------------------#
|   Preprocessor / assembler macros                                 |
#-------------------------------------------------------------------#

   Macros with multiple statements like the assembler "MACRO" macros
   are also supported. Quite useful when using PowerPC asm, but is not
   restricted to asm instructions.

   <label> MACRO
    ...
    ...
    ...
   ENDM

   Arguments are received in "\1" to "\9".
   "\0" is reserved for an optional "." / ".L" / ".W" / ".B" / ".D".

   example:

      A PowerPC asm macro:

         ROTLW MACRO -> Rotate Left Word
            RLWNM\0 \1,\2,\3,0,31
         ENDM

      Using the macro:

         ROTLW R3, R4, R5  -> produces : RLWNM R3, R4, R5, 0, 31
         ROTLW. R3, R4, R5 -> produces : RLWNM. R3, R4, R5, 0, 31
         ROTLW x,y         -> produces : RLWNM x y, 0, 31 -> error !

      A different FOR construct:

         FOR2 MACRO
            \1
            WHILE \2
         ENDM

         ENDFOR2 MACRO
               \1
            ENDWHILE
         ENDM

      Use it:

         FOR2 x := 3, x < 1000
            WriteF('x=\dn', x)
         ENDFOR2 x := x * 3

   "EXPORT" may be used:

      EXPORT COPY MACRO
         ...


   To use a MACRO, it must be the first thing on a line (white
   space not counted) or it will not be recognised as a MACRO.