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=== tests/cases/compiler/contextualSignatureInstatiationContravariance.ts ===
interface Animal { x }
>Animal : Symbol(Animal, Decl(contextualSignatureInstatiationContravariance.ts, 0, 0))
>x : Symbol(Animal.x, Decl(contextualSignatureInstatiationContravariance.ts, 0, 18))
interface Giraffe extends Animal { y }
>Giraffe : Symbol(Giraffe, Decl(contextualSignatureInstatiationContravariance.ts, 0, 22))
>Animal : Symbol(Animal, Decl(contextualSignatureInstatiationContravariance.ts, 0, 0))
>y : Symbol(Giraffe.y, Decl(contextualSignatureInstatiationContravariance.ts, 1, 34))
interface Elephant extends Animal { y2 }
>Elephant : Symbol(Elephant, Decl(contextualSignatureInstatiationContravariance.ts, 1, 38))
>Animal : Symbol(Animal, Decl(contextualSignatureInstatiationContravariance.ts, 0, 0))
>y2 : Symbol(Elephant.y2, Decl(contextualSignatureInstatiationContravariance.ts, 2, 35))
var f2: <T extends Animal>(x: T, y: T) => void;
>f2 : Symbol(f2, Decl(contextualSignatureInstatiationContravariance.ts, 4, 3))
>T : Symbol(T, Decl(contextualSignatureInstatiationContravariance.ts, 4, 9))
>Animal : Symbol(Animal, Decl(contextualSignatureInstatiationContravariance.ts, 0, 0))
>x : Symbol(x, Decl(contextualSignatureInstatiationContravariance.ts, 4, 27))
>T : Symbol(T, Decl(contextualSignatureInstatiationContravariance.ts, 4, 9))
>y : Symbol(y, Decl(contextualSignatureInstatiationContravariance.ts, 4, 32))
>T : Symbol(T, Decl(contextualSignatureInstatiationContravariance.ts, 4, 9))
var g2: (g: Giraffe, e: Elephant) => void;
>g2 : Symbol(g2, Decl(contextualSignatureInstatiationContravariance.ts, 6, 3))
>g : Symbol(g, Decl(contextualSignatureInstatiationContravariance.ts, 6, 9))
>Giraffe : Symbol(Giraffe, Decl(contextualSignatureInstatiationContravariance.ts, 0, 22))
>e : Symbol(e, Decl(contextualSignatureInstatiationContravariance.ts, 6, 20))
>Elephant : Symbol(Elephant, Decl(contextualSignatureInstatiationContravariance.ts, 1, 38))
g2 = f2; // error because Giraffe and Elephant are disjoint types
>g2 : Symbol(g2, Decl(contextualSignatureInstatiationContravariance.ts, 6, 3))
>f2 : Symbol(f2, Decl(contextualSignatureInstatiationContravariance.ts, 4, 3))
var h2: (g1: Giraffe, g2: Giraffe) => void;
>h2 : Symbol(h2, Decl(contextualSignatureInstatiationContravariance.ts, 9, 3))
>g1 : Symbol(g1, Decl(contextualSignatureInstatiationContravariance.ts, 9, 9))
>Giraffe : Symbol(Giraffe, Decl(contextualSignatureInstatiationContravariance.ts, 0, 22))
>g2 : Symbol(g2, Decl(contextualSignatureInstatiationContravariance.ts, 9, 21))
>Giraffe : Symbol(Giraffe, Decl(contextualSignatureInstatiationContravariance.ts, 0, 22))
h2 = f2; // valid because Giraffe satisfies the constraint. It is safe in the traditional contravariant fashion.
>h2 : Symbol(h2, Decl(contextualSignatureInstatiationContravariance.ts, 9, 3))
>f2 : Symbol(f2, Decl(contextualSignatureInstatiationContravariance.ts, 4, 3))
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