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Diffstat (limited to 'test/pending/pos/t2071.scala')
-rw-r--r-- | test/pending/pos/t2071.scala | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/test/pending/pos/t2071.scala b/test/pending/pos/t2071.scala new file mode 100644 index 0000000000..a96edb4cfb --- /dev/null +++ b/test/pending/pos/t2071.scala @@ -0,0 +1,14 @@ +trait Iterable[+S] +trait Box[U] + +trait A { + type T <: Iterable[S] forSome { type S <: Box[U]; type U } +} + +trait B extends A { + type T <: Iterable[S] forSome { type S <: Box[U]; type U } +} +But according to SLS, 3.5.1 Type Equivalence: Two existential types (ยง3.2.10) are equivalent if they have the same number of quantifiers, and, after renaming one list of type quantifiers by another, the quantified types as well as lower and upper bounds of corresponding quantifiers are equivalent. + +So, every existential type must be equivalent to (and conform to) itself. +Attachments |