perl -e '
my $x; sub rec { goto STOP if ++$x>10; print $x; rec()};rec();STOP:' 
12345678910
##</code><code>##

use Assembler::6502;     # fictitious module 
                         # implementing Mnemonics as subs
 
MARK:      LDX 10;
           ADD 3;
 
           macro1();     # Perl sub to include/call mnemonics 
 
           JSR SUB2;
           JMP MARK;
 
SUB2:      ...
           ...
           RET