I use Emacs to write everything. So, in the last 12 months at least C, C++, D, Haskell, Ruby, and Python. For Python I use rope and jedi. Auto-complete, goto de

I use Emacs to write everything. So, in the last 12 months at least C, C++, D, Haskell, Ruby, and Python. For Python I use rope and jedi. Auto-complete, goto definition and refactoring. For C/C++ I use my own package cmake-ide. As the name implies, it only works for cmake builds. But it does work. Similarly to Python, autocomplete, on-the-fly syntax highlighting, goto-definition, ... For D I use another one of my packages, flycheck-dmd-dub. For Haskell I can't remember now but it'll all very good. For Ruby I use flycheck, rubocop and rsense.