I propose generalizing this to also allow open our $foo, ... (to explicitly open a global filehandle; remember TIMTOWTDI) and open state $foo, ...

use warnings;
use strict;
use feature 'state';

sub xyz {
    open state $foo, '<', '/tmp/foo' or die $!;
    chomp( my $bar = <$foo> );
    close $foo;
    return $bar;
}

open our $foo, '>', '/tmp/foo' or die $!;
print $foo "Hello\n";
close $foo;

use Test::More tests=>1;
is xyz(), "Hello";         # => PASS
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the result will be a disaster reminiscent of Fahrenheit 451.

A variation on Godwin's law?