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tests/cases/conformance/types/union/unionTypeFromArrayLiteral.ts(9,5): error TS2322: Type '[number, string, string]' is not assignable to type '[number, string]'.
Source has 3 element(s) but target allows only 2.
==== tests/cases/conformance/types/union/unionTypeFromArrayLiteral.ts (1 errors) ====
// The resulting type an array literal expression is determined as follows:
// If the array literal is empty, the resulting type is an array type with the element type Undefined.
// 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.
// Otherwise, the resulting type is an array type with an element type that is the union of the types of the element expressions.
var arr1 = [1, 2]; // number[]
var arr2 = ["hello", true]; // (string | number)[]
var arr3Tuple: [number, string] = [3, "three"]; // [number, string]
var arr4Tuple: [number, string] = [3, "three", "hello"]; // [number, string, string]
~~~~~~~~~
!!! error TS2322: Type '[number, string, string]' is not assignable to type '[number, string]'.
!!! error TS2322: Source has 3 element(s) but target allows only 2.
var arrEmpty = [];
var arr5Tuple: {
0: string;
5: number;
} = ["hello", true, false, " hello", true, 10, "any"]; // Tuple
class C { foo() { } }
class D { foo2() { } }
class E extends C { foo3() { } }
class F extends C { foo4() { } }
var c: C, d: D, e: E, f: F;
var arr6 = [c, d]; // (C | D)[]
var arr7 = [c, d, e]; // (C | D)[]
var arr8 = [c, e]; // C[]
var arr9 = [e, f]; // (E|F)[]
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