How can I change some specific carps into croaks in Perl? - perl

Question

I tried to catch a carp-warning:
carp "$start is > $end" if (warnings::enabled()); )
with eval {} but it didn't work, so I looked in the eval documentation and I discovered, that eval catches only syntax-errors, run-time-errors or executed die-statements.
How could I catch a carp warning?
#!/usr/bin/env perl
use warnings;
use strict;
use 5.012;
use List::Util qw(max min);
use Number::Range;
my #array;
my $max = 20;
print "Input (max $max): ";
my $in = <>;
$in =~ s/\s+//g;
$in =~ s/(?<=\d)-/../g;
eval {
my $range = new Number::Range( $in );
#array = sort { $a <=> $b } $range->range;
};
if ( $# =~ /\d+ is > \d+/ ) { die $# }; # catch the carp-warning doesn't work
die "Input greater than $max not allowed $!" if defined $max and max( #array ) > $max;
die "Input '0' or less not allowed $!" if min( #array ) < 1;
say "#array";

Answer 1

Based on your comments, my understanding is that you would like to make carp into a fatal warning.
If it is acceptable to make all carp warnings in your target package into fatal errors you can monkey-patch carp.
Carping Package:
package Foo;
use Carp;
sub annoying_sub {
carp "Whine whine whine";
}
Main program:
use Foo;
*Foo::carp = \&Foo::croak;
Foo::annoying_sub();
If you want to limit the monkey patch to a dynamic scope, you can use local:
use Foo;
Foo::annoying_sub(); # non-fatal
{ local *Foo::carp = \&Foo::croak;
Foo::annoying_sub(); # Fatal
}

Answer 2

carp does not die but just prints a warning, so there's nothing to catch with eval or whatever. You can, however, overwrite the warn handler locally to prevent the warning from being sent to stderr:
#!/usr/bin/env perl
use warnings;
use strict;
use Carp;
carp "Oh noes!";
{
local $SIG{__WARN__} = sub {
my ($warning) = #_;
# Replace some warnings:
if($warning =~ /replaceme/) {
print STDERR "My new warning.\n";
}
else {
print STDERR $warning;
}
# Or do nothing to silence the warning.
};
carp "Wh00t!";
carp "replaceme";
}
carp "Arrgh!";
Output:
Oh noes! at foo.pl line 8
Wh00t! at foo.pl line 25
My new warning.
Arrgh! at foo.pl line 29
In almost all cases you should prefer fixing the cause of the carp instead.