I run into a strange thing in how croak() (from the Carp module) works:

#!/usr/bin/env perl

use v5.36;
use strict;
use warnings;

use Carp;

open(my $ifh, '<', 'doesnotexist.dat') or croak($!);

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This outputs:

 at carptest2.pl line 9.

But when i change croak($!) to croak("$!"), everything works as expected:

No such file or directory at carptest2.pl line 9.

Shouldn't that result in the exact same output with both variants? It certainly does so with the builtin die(), where both die($!) and die("$!") print:

No such file or directory at carptest2.pl line 9.

Do i have a basic misunderstanding on how $! works/should work or is this a bug (or workaround) with Carp?

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In reply to Carp: $! vs "$!" in croaking by cavac

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