I am NOT suggesting this, but I thought I would chime in. You can modify the stack paramaters directly:

use strict;
sub test {
    if( $_[0] =~ /regex/ ) {
        $_[1] = "match";
    }
    else {
        $_[1] = "no match";
    }
}

my $bool;

test( "foo", $bool );
print "foo: $bool\n";

test( "regex", $bool );
print "regex: $bool\n";
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That is just silly though. Use the 'vars' method mentioned above or just have your subs return a value instead of setting a global variable if that is possible.

You can also encapsulate a my'd variable and make it semi global via subroutine calls, but this is sort of silly also:

use strict;
{
    my $foo;
    sub setFoo{
        $foo = shift;
    }
    sub getFoo{
        return $foo;
    }
}
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