Perl does some internal optimization. (Various meanings can be assigned to 'some', most of which are correct.)

In particular, it can remove execution paths which will never be reached: 

chromatic$ perl -MO=Deparse
print "hi";
if (0) { print "hi" }

- syntax OK
print 'hi!';
'???';

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If you use a constant for DEBUG and set it to 0, I'm 99.8% convinced Perl will do the right thing and not even compile the debugging code.

Update: I just ran a test with a real Perl package, and it works. You might want to put your constant declaration in a BEGIN{} block, just to be on the safe side.

In reply to Re: C pre-processor by chromatic
in thread C pre-processor by Anonymous Monk

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