25 lines
872 B
TypeScript
25 lines
872 B
TypeScript
class Base { foo() { } }
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class Derived1 extends Base { bar() { } }
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class Derived2 extends Base { baz() { } }
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class Derived3 extends Base { biz() { } }
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interface Document2 {
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createElement(tagName: 'canvas'): Derived1;
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createElement(tagName: 'div'): Derived2;
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createElement(tagName: 'span'): Derived3;
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createElement(tagName: string): Base;
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}
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var d2: Document2;
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// these are ok
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var htmlElement: Base = d2.createElement("yo")
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var htmlCanvasElement: Derived1 = d2.createElement("canvas");
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var htmlDivElement: Derived2 = d2.createElement("div");
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var htmlSpanElement: Derived3 = d2.createElement("span");
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// these are errors
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var htmlElement2: Derived1 = d2.createElement("yo")
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var htmlCanvasElement2: Derived3 = d2.createElement("canvas");
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var htmlDivElement2: Derived1 = d2.createElement("div");
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var htmlSpanElement2: Derived1 = d2.createElement("span"); |