> Perl -MO=Deparse -w use strict; sub DEBUG() { 0 } sub SymRef() { "My::Package::hash" } sub PI() { 3.141592 } if( DEBUG ) { warn "Okay, we are debugging...\n"; do_lots_of_debugging_stuff(); } $My::Package::hash{key}= "value"; print SymRef->{key},$/; print PI()+5,$/; __END__ sub DEBUG () { 0; } sub SymRef () { 'My::Package::hash'; } sub PI () { 3.141592; } '???'; $My::Package::hash{'key'} = 'value'; print $My::Package::hash{'key'}, $/; print 8.141592, $/; - syntax OK