29 lines
709 B
TypeScript
29 lines
709 B
TypeScript
interface IAnimal {
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name: string;
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}
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class Giraffe {
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name = "Giraffe";
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neckLength = "3m";
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}
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class Elephant {
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name = "Elephant";
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trunkDiameter = "20cm";
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}
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function foo(animals: IAnimal[]) { }
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function bar(animals: { [n: number]: IAnimal }) { }
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foo([
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new Giraffe(),
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new Elephant()
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]); // Legal because of the contextual type IAnimal provided by the parameter
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bar([
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new Giraffe(),
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new Elephant()
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]); // Legal because of the contextual type IAnimal provided by the parameter
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var arr = [new Giraffe(), new Elephant()];
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foo(arr); // ok because arr is Array<Giraffe|Elephant> not {}[]
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bar(arr); // ok because arr is Array<Giraffe|Elephant> not {}[]
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