The limitation is not ifdef's, but -M's. use is block/file scoped. -M is the same thing as use at the top of the input file, therefore -M won't affect the module.

bla.pl
------
BEGIN { $|=1 }
use bla ();
$planet = "World\n";
print($planet);


bla.pm
------
$greet = "Hello\n";
print($greet);


>perl -Mstrict bla.pl
Hello
Global symbol "$planet" requires explicit package name at bla.pl line 
+3.
Global symbol "$planet" requires explicit package name at bla.pl line 
+4.
Execution of bla.pl aborted due to compilation errors.

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As you can see, strict did not affect the module.

In reply to Re: ifdef in modules by ikegami
in thread ifdef in modules by Anonymous Monk

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