public interface IntPredicateProxy
This interface represents an integer predicate (that is, a boolean function of an integer).
It is provided for the purpose of C# transpilation: in Java, an IntPredicate can be implemented
either as a class implementing IntPredicate, or as a lambda expression,
but this duality is not available in C#. A class that implements IntPredicate
should therefore implement this extension of the interface, so that it can be transpiled to C#.