24 lines
1.1 KiB
TypeScript
24 lines
1.1 KiB
TypeScript
// The resulting type an array literal expression is determined as follows:
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// If the array literal is empty, the resulting type is an array type with the element type Undefined.
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// Otherwise, if the array literal is contextually typed by a type that has a property with the numeric name ‘0’, the resulting type is a tuple type constructed from the types of the element expressions.
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// Otherwise, the resulting type is an array type with an element type that is the union of the types of the element expressions.
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var arr1 = [1, 2]; // number[]
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var arr2 = ["hello", true]; // (string | number)[]
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var arr3Tuple: [number, string] = [3, "three"]; // [number, string]
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var arr4Tuple: [number, string] = [3, "three", "hello"]; // [number, string, string]
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var arrEmpty = [];
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var arr5Tuple: {
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0: string;
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5: number;
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} = ["hello", true, false, " hello", true, 10, "any"]; // Tuple
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class C { foo() { } }
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class D { foo2() { } }
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class E extends C { foo3() { } }
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class F extends C { foo4() { } }
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var c: C, d: D, e: E, f: F;
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var arr6 = [c, d]; // (C | D)[]
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var arr7 = [c, d, e]; // (C | D)[]
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var arr8 = [c, e]; // C[]
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var arr9 = [e, f]; // (E|F)[]
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