There are various REPL programs for perl, as a simple google search will attest. You might take a look at them and see if any fit your needs. With Terminal::Readline (IIRC) and the eval statement, it's not too difficult to cobble something together a simple REPL. So you might start with a simple one and add whatever features you want...

A couple links that google gave me are:

• Yet another Perl REPL
• Writing a perl read-eval-print loop (REPL) - part 1
• An eight-line REPL in Perl.

...roboticus

Update: I didn't even think of CPAN which has a few interesting REPL and Shell modules. (e.g. Devel::REPL, Carp::REPL, Perl::Shell, ....)