http://www.perlmonks.org?node_id=522753

This bug is just a minor annoyance, but it can slow down debugging if one is not aware of it, so I thought I'd share. The following snippets illustrates it: 

if ( 0 ) {
  ;
}
elsif ( die __LINE__ ) {
  ;
}

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If you run it as written, the output is: 
4 at buggy.pl line 1.

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Note that the line reported by die is incorrect. The same bug exists with warn, and with warnings in general. E.g. 
use warnings;
if ( 0 ) {
  ;
}
elsif ( "$_" ) {
  ;
}
__END__
Use of uninitialized value in string at buggy.pl line 2.

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Curiously, fatal Compile-time errors don't have this problem: 
if ( 0 ) {
  ;
}
elsif ( 0/0 ) {
  ;
}
__END__
Illegal division by zero at buggy.pl line 4

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Stuff happens.

Update: the above examples were run with perl 5.8.6. I haven't looked at other versions. YMMV.

Update 2: thanks to merlyn for the clarification on compile-time vs. run-time behavior, which I originally mis-interpreted as a difference in response between non-fatal and fatal and non-fatal errors.

the lowliest monk

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