StreamClass.concat<U>(...sources: Source<U>[]): StreamClass<Exclude<U, AnyFailure>, Extract<U, AnyFailure>>
Concatenates sources in order — Elixir's Stream.concat, variadic.
await Stream.concat([1, 2], [3]).collect(); // [1, 2, 3]
StreamClass<Exclude<U, AnyFailure>, Extract<U, AnyFailure>>