(And I was only really talking of the comparison of rust v rust, not rust v c, i.e. that ordermap is faster than the built in hashmap despite not using unsafe)
Ah, sorry, you were writing about hashmaps and I was writing regexes in my IDE in background while reading this thread from time to time, probably that's why I've checked regex instead of hashmap benchmark. I even wrote this benchmark in language not listed on benchmarks game lately to compare the speed. Brain can work in interesting ways!
http://benchmarksgame.alioth.debian.org/u64q/knucleotide.htm...
(And I was only really talking of the comparison of rust v rust, not rust v c, i.e. that ordermap is faster than the built in hashmap despite not using unsafe)