Array languages (Jelly is one of them!) work at a high level of abstraction, since programming consists of applying operations to entire immutable arrays. List

Array languages (Jelly is one of them!) work at a high level of abstraction, since programming consists of applying operations to entire immutable arrays. List comprehensions are probably the closest the mainstream gets to this style. It's not as abstract as possible or anything. Most directly, there are abstractions like algebraic datatypes or macros that APL doesn't have at all. And there's a sense in which APL is very concrete: it tends to use first-order functions instead of higher-order ones like Replicate[0] instead of filter. For me the fact that an array oriented program tends to handle just a few arrays at a time makes it easier to understand what's going on. I think there are also ways in which APL programming is low-level. Going back to Jelly, it's actually a stack machine, same as Java object code, or Forth. Modern APL has tacit programming[1], which has a similar mix of mathematical purity and machine-like shuffling. I think the way APL handles array axes is similar. They are numbered, so to work with them you have to keep track of the ordering. Something like einsum that names them would be higher-level. [0] https://aplwiki.com/wiki/Replicate https://aplwiki.com/wiki/Replicate [1] https://aplwiki.com/wiki/Tacit_programming https://aplwiki.com/wiki/Tacit_programming