Regular expressions

[tluyben]

Any idea for adding regular expressions? (given that all implementations of advent of code day #3 where basically just 1 regex :)

J (TIL) has them like this;

F =: +/@([: (3 */@".@}. ])@> 'mul\(\d+,\d+\)' rxall ])

how about

`/mul\((\d+),(\d)+\)`/

which will return a list with matches

so we can do;

+/*/`/mul\((\d+),(\d+)\)`//input

for instance (look ma, no casting; \d already know it's integers obviously)

For ease of implementation, this would obviously also work:

+/*rx["mul\(\(d+),\(d+)\)"]/input

Seems that's the way most other APLs implement it.

I hacked in my own which works well;

https://gist.github.com/tluyben/fc959d7ae821c8864cf13d5af319c81e
https://github.com/tluyben/ok

Makes the solution to day 3 indeed as trivial as:

+/{*/x[2]}'rx["mul\((\d+),(\d+)\)";input]

I couldn't figure out how to make it accept arguments to the left that fast (I didn't spend a lot of time), but it works.