awesome-recursion-schemes

there are more interesting recursion schemes to traverse and aggregate with, but they are intricate to express without a powerful language and confuse small minds so aren’t worth often using. QI(I)Ts let you simultaneously declare how you witness and not just how you construct. https://github.com/passy/awesome-recursion-schemes

You're absolutely right. Recursion is tied to the shape of the data being recursed. It can be expressed a number of ways, but generally having a functor for the data type gives a lot of milage in operating over it. See https://github.com/passy/awesome-recursion-schemes for more of what I'm getting after.

> they're more restrictive (in other words, they're easier to reason about)) That's a great point. Often in my programming career, I've used the rule of least power[1]. In the looping/flow control ladder, I'd list descending * JMP/GOTO * for/while * map/filter/reduce If a problem only needs a map, using a for introduces needless complexity(ie: state). Personally, I think we have a pedagogical problem in that we teach people loops first and people confuse what they've been taught first with what is a reasonable choice[2]. For completeness, recursion has it's own ladder * PUSH,POP,JMP * function call * recursion schemes[3] Side note: recursion schemes have an enormous hurdle to adoption in that mathematicians got there first and the naming are so off putting that no one will take you serious if you bring up even simple schemes like anamorph