clever vs. insightful code

hillel wayne

c send(to, from, count) register short *to, *from; register count; { register n = (count + 7) / 8; switch (count % 8) { case 0: do { *to = *from++; case 7: *to = *from++; case 6: *to = *from++; case 5: *to = *from++; case 4: *to = *from++; case 3: *to = *from++; case 2: *to = *from++; case 1: *to = *from++; } while (–n > 0); } } ```

This code is “clever” because it exploits knowledge about the language, in this case the peculiarities of fall-through. Clever code can also exploit knowledge about the operating environment or special topics like bit twiddling. Conventional wisdom says this clever code is “bad”.

There’s a second kind of “clever code”: code which exploits knowledge about the problem.

clever is specifc, niche knowledge about the material or the problem which cannot be extended to another material or problem (respectively) -> acknowledging contextual constraints

in the case of exploiting the problem, that often means that the problem is made simpler, and so the code is made simpler -> that’s insightful

but if the problem changes, that insight might disappear: such a code is read-only because relies on tacit knowledge and doesn’t transfer between people

Expert C programmers argue they don’t need memory safety, expert Clojurists argue that static types wouldn’t help them, etc.