tests/cases/compiler/contextualSignatureInstatiationContravariance.ts(8,1): error TS2322: Type '<T extends Animal>(x: T, y: T) => void' is not assignable to type '(g: Giraffe, e: Elephant) => void'.
  Types of parameters 'y' and 'e' are incompatible.
    Type 'Elephant' is not assignable to type 'Giraffe'.
      Property 'y' is missing in type 'Elephant'.


==== tests/cases/compiler/contextualSignatureInstatiationContravariance.ts (1 errors) ====
    interface Animal { x }
    interface Giraffe extends Animal { y }
    interface Elephant extends Animal { y2 }
    
    var f2: <T extends Animal>(x: T, y: T) => void;
    
    var g2: (g: Giraffe, e: Elephant) => void;
    g2 = f2; // error because Giraffe and Elephant are disjoint types
    ~~
!!! error TS2322: Type '<T extends Animal>(x: T, y: T) => void' is not assignable to type '(g: Giraffe, e: Elephant) => void'.
!!! error TS2322:   Types of parameters 'y' and 'e' are incompatible.
!!! error TS2322:     Type 'Elephant' is not assignable to type 'Giraffe'.
!!! error TS2322:       Property 'y' is missing in type 'Elephant'.
    
    var h2: (g1: Giraffe, g2: Giraffe) => void;
    h2 = f2; // valid because Giraffe satisfies the constraint. It is safe in the traditional contravariant fashion.