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/*
* @test /nodynamiccopyright/
* @bug 8016081 8016178
* @summary structural most specific and stuckness
* @compile/fail/ref=T8016177c.out -XDrawDiagnostics T8016177c.java
*/
class T8016177c {
interface Function<X, Y> {
Y m(X x);
}
interface ExtFunction<X, Y> extends Function<X, Y> { }
<U, V> U m1(Function<U, V> f) { return null; }
<U, V> U m1(ExtFunction<U, V> f) { return null; }
void m2(Function<Integer, Integer> f) { }
void m2(ExtFunction<Integer, Integer> f) { }
void m3(Function<Integer, Integer> f) { }
void m3(ExtFunction<Object, Integer> f) { }
int g1(Object s) { return 1; }
int g2(Number s) { return 1; }
int g2(Object s) { return 1; }
void test() {
m1((Integer x)->x); //ok - explicit lambda - subtyping picks most specific
m2((Integer x)->x); //ok - explicit lambda - subtyping picks most specific
m3((Integer x)->x); //ok - explicit lambda (only one applicable)
m1(x->1); //ok - stuck lambda but nominal most specific wins
m2(x->1); //ok - stuck lambda but nominal most specific wins
m3(x->1); //ambiguous - implicit lambda & different params
m1(this::g1); //ok - unambiguous ref - subtyping picks most specific
m2(this::g1); //ok - unambiguous ref - subtyping picks most specific
m3(this::g1); //ambiguous - both applicable, neither most specific
m1(this::g2); //ok - stuck mref but nominal most specific wins
m2(this::g2); //ok - stuck mref but nominal most specific wins
m3(this::g2); //ambiguous - different params
}
}
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