import java.util.List;
import java.util.ArrayList;
import java.lang.Integer;
import java.lang.System;
import java.io.PrintStream;
import java.util.stream.Stream;
import java.util.function.Function;

public class Bug298 {
    public <R, T> Stream<R> takes(Stream<T> s, Function<? super T, ? super R> fun) {
        return null;
    }

    public void m() {
        List<Integer> list = new ArrayList<>();
        Stream<Integer> a = list.stream();
        takes(a, x -> 2 * x);
    }
}