Like slime, if you ignore autocompletion, arglist hints, automatic indentation of macros based on &body, M-. (jump to definition), crossreferencing, and compiler note overlays.
It is close, but I would have to say that the way emacs interacts with external processes is probably my favorite feature. It is simply a paradigm that no other text editor seems to even attempt.
Here are some common modes that I use that interact with external processes.
py-shell: kind of obvious, using the python shell is sometimes awkward because of the way that python doesn't reload code.
pdb-mode:in any shell process, if my python code hits a pdb.set_trace() python will pop up a debugging repl. As I step through my code with pdb, emacs opens up whatever file the current stack is in to the position in the stack. I couldn't imagine debugging code without this. This functionality also exists for gdb and rdb I think, I don't use those frequently.
compile-mode: when I run unit tests and I get an error, compile mode lets me click or hit return on that error and instantly jump to that code in another buffer
shell: emacs deals with my bash shell. I can easily scroll up in the buffer to copy and paste output from previous commands. I can search backwards through not just commands I have previously run, but through previous output from the shell. When I open a file from the shell, it defaults to my current shell directory.
sql-mode: gives all the goodness of emacs to an sql repl. I can edit sql in another buffer, craft the query I want, and send just that query to my sql repl.
I'm not an emacs fan either but I grudgingly use it everyday for R and Octave development. Vim is my preferred text editor but it can't compare to the power of emacs when working with interactive languages. Emacs viper mode is excellent though and gives access to the vi keys anywhere. I'd also recommend those that really hate emacs to try the console mode -- its much snappier and brings the monster closer to a vim-like experience.
Overall, great idea. However, it's kind of annoying to use with Python, since when you copy in a function definition, you need to go to the interpreter and hit enter an extra time to get it to work. I was going to try and fix this myself, but I'm not sure if there's any easy way to add a special case for this, since the Vim script has no way of knowing what kind of interpreter is running in the other screen session....
This is cool, but kinda hacky... I mean what if I want to use the output for say, going to the error in the copied code? Does screen have a way to attach to stdin/stdout/stderr for a process it is running? While still displaying in the host terminal as well (something akin to tee)?
I had trouble installing it, actually.. I couldn't seem to get the plugin to load the keybindings (LocalLeader never seemed to have got bound and the functions which were to get called werent defined..) :-(
Its a pity, because VimClojure looks damned sweet. Thankfully I did get VimClojures syntax highlighting to work.
I had the same issue at first. I did get it fixed eventually but I can't remember what I did. :-( Once you get it running though it offers syntax completion send-to-repl and most of the slime functionality without the need for screen. Very worth the effort setting it up.
This also reminds me a bit of projects along the lines of "Like Lisp, for <some non-Lisp language>!" Yes, just like it, except missing most of the good parts.
But having C-c C-c is nice!