flatMapFirst<R, A> function
Composes computations in sequence, using the return value from the previous computation, discarding the result.
Implementation
Reader<R, A> Function(Reader<R, A>) flatMapFirst<R, A>(
Reader<R, dynamic> Function(A a) f,
) =>
flatMap((a) => Reader((r) {
f(a)(r);
return a;
}));