Comment by dkersten

I've been using Max/MSP lately and while I find the language itself lacking (one example of something I wish I could do is nested lists), the editor is amazing. The live programming is ahead of any normal REPL I've used and the debugger is pretty cool too.

If it had a few extra features it would make it pretty close to my ideal programming environment: a way of (temporarily) disabling selected code; a unit testing mechanism and a way of extracting selected code to a unit test; a visual code diff tool; git integration (especially branches)