Re:Chez Scheme is now free
by nickpsecurity on Wednesday April 27, 2016 @01:00AM
(#11577927)
Or LispWorks or Franz Allegro (esp AllegroCache) that have made real money for years by letting people code circles around others with better tooling. Scripting languages have closed the gap a lot but not fully. I'd say at least two commercial tools are quite practical.
Emacs Lisp is probably a better example of practical.