run rust as script

rustrun

#!/bin/sh
SELF="$1"
MD5=$(md5sum "${SELF}" | cut -f1 -d" ")
OUT="${SELF}.${MD5}.out"
if [ ! -f "${OUT}" ]; then
    rustc -C debuginfo=0 -C prefer-dynamic "${SELF}" -o "${OUT}" || exit 1
fi

shift
exec "${OUT}" "$@"

E.g.:

#!/usr/local/bin/rustrun

fn main() {
  println!("Hello, world!");
}

Then chmod a+x hello.rs and run ./hello.rs.