Overriding one instance's methods at runtime is not directly possible, unless I'm mistaken (which is entirely possible and often even likely). What you could do is provide your own subclass of Apache::FakeRequest that overrides that method, and use that as the class of your object: 
package Apache::FakeRequest::ViceRaid;
use base qw(Apache::FakeRequest);
sub lookup_uri {
  # do your stuff.
}

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In your actual script, you'd use something like my $req=Apache::FakeRequest::ViceRaid->new() to instantiate your derived object.

The non-lvalue error means that you're assigning something to something else that cannot be assigned to. Things that you can assign to are lvalues, thus things that you can't assign to are non-lvalues. E.g.: 

$ perl -e 'sub nonlvalue { return }; nonlvalue()=1;'
Can't modify non-lvalue subroutine call in scalar assignment at -e lin
+e 1, near "1;"

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The nonlvalue subroutine is not an lvalue, so you get the error when you want to assign to it. perlsub has some information on how to make a subroutine return an lvalue.

CU
Robartes-

In reply to Re: changing object's methods at runtime by robartes
in thread changing object's methods at runtime by ViceRaid

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