That's right, moreover it provides sub routine name from where croak called. This is better way to catch error.

Very well put. Thank you.

When you call die and give it a message that doesn't end with a newline, perl helpfully tacks on the file and line where you called die. Carp provides the 'croak' function, which does essentially the same thing, except instead of telling you the file and line where you called croak, it tells you the file and line where the function containing the croak was called.

#!/usr/bin/perl -w
use strict; use warnings;
use Carp qw( croak );

do_something();

sub do_something {
    croak "croaked!";
}
__END__
croaked! at test10.pl line 8
    main::do_something() called at test10.pl line 5
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#!/usr/bin/perl -w
use strict; use warnings;
use Carp qw( croak );

do_something();

sub do_something {
    die "died!";
}
__END__
died! at test10.pl line 8.
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The preferred one is whichever gives you the effect you desire. When writing modules I generally to use die for fatal errors that indicate something is wrong with the method that I'm calling die from, so that the error message points at that method, but use croak for fatal errors that indicate that the method was used incorrectly, so that the error message points towards the caller of the method, rather than the method itself.

Given the monastic nature of the place you might also look into confess (another function from Carp). When dealing with deep code -- in legacy territory where one module calls into a chain of several others which in turn each have some half-baked pointless inheritance scheme -- it can be a sanity saver.

Amen!

Frankly, most bugs are easy to resolve once you find them. “Aye, there's the rub...” So these routines give you a traceback.

>perldoc -f croak
No documentation for perl function `croak' found


>perldoc -f die
    die LIST
            Outside an "eval", ...

>perldoc Carp
...
DESCRIPTION
    The Carp routines are useful in your own modules because they act 
+like
    die() or warn(), but with a message which is more likely to be use
+ful to
    a user of your module. ...
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