Unless i am missing something (i most always am), would Test::MockObject be useful here? 
use Test::More qw(no_plan);
use Test::MockObject;
# use Roman;    # <- i don't have Roman.pm installed

my $roman = Test::MockObject->new();

$roman->set_true($_) for qw(roman isroman arabic);
ok($roman->isroman('IV'));

$roman->set_false('isroman');
ok($roman->isroman('42'));

[download]
or am i missing something?

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: RFC: Preventing a module from loading by jeffa
in thread RFC: Preventing a module from loading by Corion

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