I have seen that Rust is lucky to be on this site (unfortunately unlike D language):
I am not yet good enough to improve/write BenchmarksGame Rust entries. That site ranks languages according to run-time and also to de-commented&compressed code length. That site allows multiple entries for each language, so I suggest to put there two or more entries for each Rust benchmark, one entry designed to be short or/and idiomatic, and a second version designed just for speed. This allows to better see the various balances Rust offers to the programmer.
Example: this version is as fast as the best C entry, but it’s quite ugly looking and quite long (and it uses more memory than the C entry):
I am not suggesting to remove or rewrite that Rust entry, but I suggest to add a second shorter and much nicer entry, using the num bigints, and it should be as nice and short as this one (this Python3 entry also uses GMP, so it’s just 1.3 times slower than the Rust entry):
I am still rather new to Rust, but while I learn Rust I’ll probably write, improve, fix and update some RosettaCode (http://rosettacode.org ) entries. For me it’s a way to learn many corners of a language, and the resulting examples (if they are well written) are useful for other Rust newbies.