8 ms·

I don't think user-level definitions of custom symbols are that useful, but for what it's worth, you can do it in ngn/k... (Π):!/: / make table Π

I don't think user-level definitions of custom symbols are that useful, but for what it's worth, you can do it in ngn/k... (Π):!/: / make table Π[`a `b ( 1 2 3 4)]

mlajtos 3y ago
TIL that ngn/apl and ngn/k supports user-defined symbols. Thank you! Creating custom notation (aka DSL) can be very liberating. As Iverson noted, having a good notation enables you to think previously unthinkable thoughts. Einstein’s theory of relativity was enabled by use of his sum notation. [0] Of course, it should be paired with the right user interface. Inputting non-ASCII chars on keyboards is still pretty cumbersome. But APL with its weird symbols is perfect for paper and pencil, where it has its origins. [1] Some might see pencil-and-paper interface for an array-oriented REPL as going backwards, but I consider pencil to be mightier than the keyboard. Finally you could sketch visually your algorithm beside the runnable code. [0]: https://en.m.wikipedia.org/wiki/Einstein_notation https://en.m.wikipedia.org/wiki/Einstein_notation [1]: https://mlajtos.mu/posts/new-kind-of-paper https://mlajtos.mu/posts/new-kind-of-paper