If each type in U has a property P, U has a property P of a union type of the types of P from each type in U.
18 lines
514 B
TypeScript
18 lines
514 B
TypeScript
// A | B is equivalent to A if B is a subtype of A
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class C { }
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class D extends C { foo() { } }
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var x: C;
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var x : C | D;
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// A | B is equivalent to B | A.
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var y: string | number;
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var y : number | string;
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// AB | C is equivalent to A | BC, where AB is A | B and BC is B | C.
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var z : string | number | boolean;
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var z : (string | number) | boolean;
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var z : string | (number | boolean);
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var AB : string | number;
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var BC : number | boolean;
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var z1: typeof AB | boolean;
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var z1: string | typeof BC;
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