I would expect any of the following:
hello,hi,othello,brake,rake,raker,rash,ash,hash,ohio,
the,lob,bra,hell,era
I don't see how you could expect some of those strings, because some only appear once in the string (e.g. "othello", "ohio"), so you really couldn't call them a "pattern" unless you're matching against a dictionary file.
My solution near the top of this thread sort of assumes that the string is a contiguous series of patterns (one of the original constraints was "String contains nothing but patterns"), so it only finds "hello" from your test string, but if you change this line:
# From this
if (/\G(.{2,})(?=.*?\1)/g) {
# To this
if (/\G.*?(.{2,})(?=.*?\1)/g) {
Then it does better and finds "ash", "rake", and "hello" from your test string, which is about as good as it gets, I believe.
