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  1. trait B
  2. trait D extends B
  3.  
  4. object Main extends App {
  5. 	val x: (D => Any) => Any = null
  6. 	val y: (B => Any) => Any = x // compiles; covariant in D
  7.  
  8. 	// val a: D => Any = null
  9. 	// val b: B => Any = a // doesn't compile; contravariant in D
  10. }
Success #stdin #stdout 0.24s 381632KB
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https://ideone.com/LSGjjC
language:
Scala (scala 2.12.8)
created:
9 years ago
visibility:
public

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