Shell under Wx

I really want a Perl REPL inside Decl, but in a Wx or other GUI environment, I want to be able to put it into a separate window. Until now, somehow I've managed never to be able to figure out how it's done. But there is a CPAN shell in such a Wx app. What I really want, then, is to do that, but for a generic shell. (There is also such a thing for Tk, by the way.)

In the larger scheme of things, it would be nice to be able to define the "operating environment" in some way, and pop up semantically specified things like "a shell" in a way that's appropriate to that environment. In a remote context, it could even be some kind of AJAX thing. (I know it's no longer de rigeur to call it AJAX, but hey, I'm old.)

While researching it this time, I also ran across the kitchen-sink REPL Devel::REPL, based on Moose and importing lots of stuff, and PPI, which is a Perl kind-of parser that looks pretty darned interesting.