I can't imagine how one would write something like Slime without really digging into Vim's internals (written in C). I challenge you to point me to any Vim plu

I can't imagine how one would write something like Slime without really digging into Vim's internals (written in C). I challenge you to point me to any Vim plug-in (for any language) that provides a REPL like command-line, objection inspection, debugging, etc. without using C to directly mess with Vim's innards.