1 2peg::parser!{ 3 pub grammar list_parser() for str { 4 rule number() -> u32 5 = n:$(['0'..='9']+) {? n.parse().or(Err("u32")) } 6 7 pub rule list() -> Vec<u32> 8 = "[" l:(number() ** ",") "]" { l } 9 } 10 }