13 lines
396 B
Java
13 lines
396 B
Java
sealed interface List<T> permits Cons, Empty {}
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record Cons<T>(T a , List<T> l ) implements List <T> {}
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record Empty<T>() implements List <T> {}
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public class Bug380 {
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public <T> List<T> append(List<T> l1, List<T> l2) {
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return switch ( l1 ) {
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case Cons(e, rest) -> new Cons<>(e, append(rest, l2)); //::Typ TPH A
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case Empty() -> l2;//::TPH B
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};
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}
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}
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