Resub (Regex Substitution or Repeated Substitution) is an esoteric programming language where programs are composed entirely of regular expressions and the only control flow operation is regex substitute. It's not very easy to program in...
>resub lib/sqrt.re lib/decode.re
Loaded 216 transformation rules.
?> sqrt/1 169
5278 transformation rules applied; completed in 0.59s.
13
?> sqrt/1 4819136400
27041 transformation rules applied; completed in 2.75s.
69420
?> decode/1 sqrt/1 98151623087692571623976236910206979821391529
738949 transformation rules applied; completed in 383.92s.
Go Resub!
?>(this relies on the Resub programs sqrt.re and decode.re in lib—I highly encourage you to go check them out, sqrt.re in particular. Writing a O((log_{10}n)^3) sqrt in regexes was a very interesting challenge!)
I wanted to see if a bunch of regular expressions in a while loop can compute square roots. Turns out it can!
See EXAMPLE.md