Mind Bending Stuff

I am just getting my head around this (pdf) comment on the problem at the last ICFP Programming Contest , anyone who likes puzzles, compilers and reverse engineering should take a look, I am amazed by how rich this problem was. The ICFP do not specify what counts as “functional”, but OCaml and Haskell usually do very well in the contest. This year a C++ team won it and a perl team came second, after lots of teams abandoned their functional languages. The authors make the point that data structure design/choice is very important (which we all should know I suppose), they recommend Data.sequence in Haskell and I think it is similar to a Rope (sort of tree based string representation that makes concatenation a snip, wikipedia is weak on it but Ruby Quiz mentioned it a few weeks ago)