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Why is this lambda illegal? - Java Community | Help. Code. Learn.

Java Community | Help. Code. Learn.•3y ago•

30 replies

Why is this lambda illegal?

hey guys. can smb explain lambdas to me? what am i doing wrong?

public interface FunctionalInterface {
    String function(String str);
}
public class Main {
    public static void main(String[] args) {
        FunctionalInterface functionalInterface= "hello"->"hello";
    }
}

public interface FunctionalInterface {
    String function(String str);
}
public class Main {
    public static void main(String[] args) {
        FunctionalInterface functionalInterface= "hello"->"hello";
    }
}

My lambda complies to the functional interface. Its argument is of String type, and it returns String too. wt f?