I don't understand your question. Do you mean Perl should warn when you pass a closed filehandle to a subroutine?

There's nothing inherently wrong in passing a filehandle: 

#!/usr/bin/perl
use warnings;
use strict;

main(@ARGV);

sub main {
    my ($file1, $file2) = @_;
    open my $fh, '<', $file1 or die $!;
    print "first: $_" while <$fh>;
    close $fh;

    again($fh, $file2);
    print "again: $_" while <$fh>;
}

sub again {
    my ($fh, $name) = @_;
    open $fh, '<', $name or die $!;
}

[download]

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: Propose addition to use warnings? by choroba
in thread Propose addition to use warnings? by perldigious

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