3 ms·

I haven't tried the others, but J meets all those requirements.

• RodgerTheGreat 8mo ago
  Yep. J has a small userbase, but it isn't fragmented into dialects like K or even APL, J uses ASCII characters instead of requiring a custom font/keyboard layout, J is FOSS, J has extensive learning materials, and J is reasonably batteries-included and suitable for making practical nontrivial programs. I like K better than J aesthetically, but it's harder to recommend to beginners due to the fragmentation of the ecosystem.
• kstrauser 8mo ago
  I keep getting nudged in that direction. I'll check it out, thanks!