Instaparser is an easy to use parser in Clojure I have been using to create simple external DSLs. Grammars can be defined using standard EBNF or ABNF notation for context-free grammars:
S = AB* AB = A B A = 'a'+ B = 'b'+
My grammars are simple, so my priority is easy of use. Are there a parser similar to instaparser for Rust?