Any white space separated rule element is considered a sequence. Each rule in the sequence is matched from the input stream, consuming the input as it goes. The AST result is a vector containing the results of each rule element in the sequence.

USING: prettyprint peg.ebnf ; "abbba" EBNF[[ rule="a" ("b")* "a" ]] .
V{ "a" V{ "b" "b" "b" } "a" }