# APL Is Really Cool

It's a REPL interface, and a really old one. But it's all about performing abstract operations on concrete data. Reminds me of PANE's philosophy: "programming with visible data".

The weird runic incantations like r←,⍳⊢ ⋄ (r G) ≡ r ∘.{⍺[⍵]}⍨ ↓r G are super charming as well. Sure it's intimidating to look at, but the semantics could perhaps be turned into direct manipulation semantics (theory.interaction-semantics)?

Here's a bunch of college-level math textbooks where the examples are in APL. All by Iverson(?).

Teaching Mathematics Using APL

(related: rethinking-media.microworld-languages)