Excuse me, but in my programming thought flow, there are checksums and limits, not c's and l's, and my code reflects that. Do I not qualify as a coder?
It was a quick prototype written by one APLer, for another APLer, using mutually understood conventions. For example, its dyadic verbs ("V2" functions) use the variable names 'a' and 'w'. For a while, I wondered why (maybe they stood for "Arthur" and "Whitney"?), but after reading Iverson's _A Programming Language_, I realized APL usually uses lowercase alpha (α) and omega (ω), which look like 'a' and 'w' in ASCII. Details like that would need no explanation.
Likewise, in
typedef struct a{I t,r,d[3],p[2];}*A;
APL code is often terse to the point of seeming cryptic, just math papers are. You get used to it, and it's that way for a reason.
My immediate reaction on seeing the page was recoil and puzzlement: it looked nothing like any C code I had ever seen. (“Is it even C?”) However, Ken counselled that I should reserve judgment. As recounted in An Implementation of J, it then happened that:
I studied this interpreter for about a week for its organization and programming style; and on Sunday, August 27, 1989, at about four o’clock in the afternoon, wrote the first line of code that became the implementation described in this document.
The name “J” was chosen a few minutes later, when it became necessary to save the interpreter source file for the first time.
Like Emacs, J's internal documentation is excellent, but you have to learn its idiosyncratic terminology before you can actually find things.
I, for one, am happy simply finding the code 'of interest'. It's not great code, it's the initial sketch of an idea (I'll bet you AW would admit that readily (plus Roger Hui refers to it as "Incunabulum", which seems a bit tongue in cheek)) -- but, it's certainly not something you see every day, and it is thought provoking.