> (...) Richard Stallman, founder of the GNU Project, was an early adopter of APL, using it to write a text editor as a high school student in the summer of 1969.
And:
Rho, rho, rho of X
Always equals 1
Rho is dimension, rho rho rank.
APL is fun!
Richard M. Stallman, 1969
https://en.wikipedia.org/wiki/APL_(programming_language)#GNU...
> (...) Richard Stallman, founder of the GNU Project, was an early adopter of APL, using it to write a text editor as a high school student in the summer of 1969.
And:
https://www.gnu.org/software/apl/But:
> GNU APL was written and is being maintained by Jürgen Sauermann.
and I believe it's fairly young when compared to emacs/emacs lisp.