Without using a text preprocessor or waiting for Perl 6's lazy evaluation, I don't see an easy way to turn off checking by throwing a switch. The switch would be present in each statement: if ($debug && expensive_sanity_check(x)) ...
Use a constant:
  
use constant DEBUG => 0;
...
sub foo {
  sanity_check(...) if DEBUG;
}

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This has the nice effect of optimizing away the entire sanity check statement in production code, without employing a preprocessor/text-filter. 
   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

In reply to (MeowChow) Re2: Pre and Post Condition by MeowChow
in thread Pre and Post Condition by E-Bitch

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