True. I taught myself C using vim + gcc under Linux. For those wondering what exactly you learn:

1. You learn the command line interface to your compiler, which is invaluable and something you'll have to learn at some point, even if you start off on an IDE.

2. Similarly you learn the command line interface to the compiler's support tools like make, linker, debugger, profiler, source code revision control, grep, strings and so on, and more importantly how the whole process of 'write-compile-execute-debug' cycle is done.

I learned how to program without an IDE, and I'm a pretty big fan of it. And strongly typed functional languages with type inference tend to be really easy to write and refactor without needing specialized IDE tasks for the job.

That being said, nowadays I use an IDE because it is extremely helpful to have autocomplete (which is okay with Racer+Vim, but kinda hacky) as well as the hover for type information (name of types, type signature, etc.). Without the hover information, I usually end up doing ridiculous things like writing bogus explicit types to see what type an undocumented function from a library will return after compiling (Is it Option? or Result?). That is really annoying.

I didn't downvote you BTW.

[this post was wrong]

Isn't it the other way around? One can downvote a post and then reply to it, but can't downvote replies to one's own post?

Gah, you're right.

I have programmed without an IDE. What I learned was that I'm much more productive with one then without.

An IDE lets me focus on the problem, not the language.

I have worked for years without an IDE because there where none.

What exactly is there to learn? That you have to spend more valuable time on memorizing unimportant things?

There are now some pretty decent autocomplete plugins for emacs, so it is possibly an option if you already an emacs user. But emacs is emacs.