48 lines
1.5 KiB
TypeScript
48 lines
1.5 KiB
TypeScript
//// [objectLiteralContextualTyping.ts]
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// In a contextually typed object literal, each property value expression is contextually typed by
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// the type of the property with a matching name in the contextual type, if any, or otherwise
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// for a numerically named property, the numeric index type of the contextual type, if any, or otherwise
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// the string index type of the contextual type, if any.
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interface Item {
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name: string;
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description?: string;
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}
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declare function foo(item: Item): string;
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declare function foo(item: any): number;
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var x = foo({ name: "Sprocket" });
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var x: string;
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var y = foo({ name: "Sprocket", description: "Bumpy wheel" });
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var y: string;
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var z = foo({ name: "Sprocket", description: false });
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var z: number;
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var w = foo({ a: 10 });
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var w: number;
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declare function bar<T>(param: { x?: T }): T;
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var b = bar({});
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var b: {};
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//// [objectLiteralContextualTyping.js]
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// In a contextually typed object literal, each property value expression is contextually typed by
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// the type of the property with a matching name in the contextual type, if any, or otherwise
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// for a numerically named property, the numeric index type of the contextual type, if any, or otherwise
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// the string index type of the contextual type, if any.
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var x = foo({ name: "Sprocket" });
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var x;
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var y = foo({ name: "Sprocket", description: "Bumpy wheel" });
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var y;
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var z = foo({ name: "Sprocket", description: false });
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var z;
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var w = foo({ a: 10 });
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var w;
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var b = bar({});
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var b;
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