WhereParserExtension<T> extension Null safety



where(Predicate<T> predicate, {Callback<T, String>? failureMessage, Callback<T, int>? failurePosition}) Parser<T>
Returns a parser that evaluates the predicate with the successful parse result. If the predicate returns true the parser proceeds with the parse result, otherwise a parse failure is created using the optionally specified failureMessage and failurePosition callbacks. [...]