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=== tests/cases/compiler/partiallyDiscriminantedUnions.ts ===
// Repro from #10586
interface A1 {
type: 'a';
>type : "a"
subtype: 1;
>subtype : 1
}
interface A2 {
type: 'a';
>type : "a"
subtype: 2;
>subtype : 2
foo: number;
>foo : number
}
interface B {
type: 'b';
>type : "b"
}
type AB = A1 | A2 | B;
>AB : AB
const ab: AB = <AB>{};
>ab : AB
><AB>{} : AB
>{} : {}
if (ab.type === 'a') {
>ab.type === 'a' : boolean
>ab.type : "a" | "b"
>ab : AB
>type : "a" | "b"
>'a' : "a"
if (ab.subtype === 2) {
>ab.subtype === 2 : boolean
>ab.subtype : 1 | 2
>ab : A1 | A2
>subtype : 1 | 2
>2 : 2
ab.foo;
>ab.foo : number
>ab : A2
>foo : number
}
}
// Repro from #11185
class Square { kind: "square"; }
>Square : Square
>kind : "square"
class Circle { kind: "circle"; }
>Circle : Circle
>kind : "circle"
type Shape = Circle | Square;
>Shape : Shape
type Shapes = Shape | Array<Shape>;
>Shapes : Shapes
function isShape(s : Shapes): s is Shape {
>isShape : (s: Shapes) => s is Shape
>s : Shapes
return !Array.isArray(s);
>!Array.isArray(s) : boolean
>Array.isArray(s) : boolean
>Array.isArray : (arg: any) => arg is any[]
>Array : ArrayConstructor
>isArray : (arg: any) => arg is any[]
>s : Shapes
}
function fail(s: Shapes) {
>fail : (s: Shapes) => void
>s : Shapes
if (isShape(s)) {
>isShape(s) : boolean
>isShape : (s: Shapes) => s is Shape
>s : Shapes
if (s.kind === "circle") {
>s.kind === "circle" : boolean
>s.kind : "square" | "circle"
>s : Shape
>kind : "square" | "circle"
>"circle" : "circle"
let c: Circle = s;
>c : Circle
>s : Circle
}
}
}
|
