Many programs out there already rely on being able to use a URI::URL object as a scalar… ie. 'print if $uri =~ /pdf\s+$/;’ Is there any way to control the value returned when an object is used in a scalar context?

You can overload the "" (stringification) operation:

package Pkg;

use overload '""' => sub { "[[[" . $_[0]->{val} . "]]]" };

package Main;

my $x = { val => '10' };
bless $x, Pkg;

print $x;
#  [[[10]]]
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