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import java.util.List;
import java.util.function.Function;
 
class Test {
    interface Mapper<T, U extends MapperProvider<U>> extends Function<T, U> {}
 
    interface MapperProvider<V> {
    	Mapper<V, ?> provide();
    }
 
    private <V extends MapperProvider<V>> void use(V c) {
    	use2(c.provide().apply(c));
    }
 
    private <W extends MapperProvider<W>> void use2(W c) {
    }
}

Main.java:12: error: method use2 in class Test cannot be applied to given types;
    	use2(c.provide().apply(c));
    	^
  required: W
  found: CAP#1
  reason: inference variable W has incompatible bounds
    equality constraints: CAP#1
    lower bounds: MapperProvider<CAP#1>
  where W is a type-variable:
    W extends MapperProvider<W> declared in method <W>use2(W)
  where CAP#1 is a fresh type-variable:
    CAP#1 extends MapperProvider<CAP#1> from capture of ?
1 error

Standard output is empty