[smartmic]

It would be good if the APL dialect in which this is implemented is mentioned on the front page. I implemented some things in GNU APL which is an (almost) complete implementation of ISO standard 13751, based primarily on APL2. More common and modern is the proprietary Dyalog APL, which I assume is used here (and which is also free for personal use).

[abrudz]

It is indeed Dyalog APL (evident by certain features used, and also what Co-dfns requires). And yes, I agree, especially since this uses the ".apl" file extension of GNU APL, rather than the ".apls" that Dyalog uses for shell scripts. Oddly enough, the "⎕IO←0" appears outside the ":Namespace" which means it cannot be used by other APL code.

[skruger]

It is Dyalog APL.