File: typeGuardFunction.types

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=== tests/cases/conformance/expressions/typeGuards/typeGuardFunction.ts ===
class A {
>A : A

    propA: number;
>propA : number
}

class B {
>B : B

    propB: number;
>propB : number
}

class C extends A {
>C : C
>A : A

    propC: number;
>propC : number
}

declare function isA(p1: any): p1 is A;
>isA : (p1: any) => p1 is A
>p1 : any

declare function isB(p1: any): p1 is B;
>isB : (p1: any) => p1 is B
>p1 : any

declare function isC(p1: any): p1 is C;
>isC : (p1: any) => p1 is C
>p1 : any

declare function retC(): C;
>retC : () => C

var a: A;
>a : A

var b: B;
>b : B

// Basic
if (isC(a)) {
>isC(a) : boolean
>isC : (p1: any) => p1 is C
>a : A

    a.propC;
>a.propC : number
>a : C
>propC : number
}

// Sub type
var subType: C;
>subType : C

if(isA(subType)) {
>isA(subType) : boolean
>isA : (p1: any) => p1 is A
>subType : C

    subType.propC;
>subType.propC : number
>subType : C
>propC : number
}

// Union type
var union: A | B;
>union : A | B

if(isA(union)) {
>isA(union) : boolean
>isA : (p1: any) => p1 is A
>union : A | B

    union.propA;
>union.propA : number
>union : A
>propA : number
}

// Call signature
interface I1 {
    (p1: A): p1 is C;
>p1 : A
}

// The parameter index and argument index for the type guard target is matching.
// The type predicate type is assignable to the parameter type.
declare function isC_multipleParams(p1, p2): p1 is C;
>isC_multipleParams : (p1: any, p2: any) => p1 is C
>p1 : any
>p2 : any

if (isC_multipleParams(a, 0)) {
>isC_multipleParams(a, 0) : boolean
>isC_multipleParams : (p1: any, p2: any) => p1 is C
>a : A
>0 : 0

    a.propC;
>a.propC : number
>a : C
>propC : number
}

// Methods
var obj: {
>obj : { func1(p1: A): p1 is C; }

    func1(p1: A): p1 is C;
>func1 : (p1: A) => p1 is C
>p1 : A
}
class D {
>D : D

    method1(p1: A): p1 is C {
>method1 : (p1: A) => p1 is C
>p1 : A

        return true;
>true : true
    }
}

// Arrow function
let f1 = (p1: A): p1 is C => false;
>f1 : (p1: A) => p1 is C
>(p1: A): p1 is C => false : (p1: A) => p1 is C
>p1 : A
>false : false

// Function type
declare function f2(p1: (p1: A) => p1 is C);
>f2 : (p1: (p1: A) => p1 is C) => any
>p1 : (p1: A) => p1 is C
>p1 : A

// Function expressions
f2(function(p1: A): p1 is C {
>f2(function(p1: A): p1 is C {    return true;}) : any
>f2 : (p1: (p1: A) => p1 is C) => any
>function(p1: A): p1 is C {    return true;} : (p1: A) => p1 is C
>p1 : A

    return true;
>true : true

});

// Evaluations are asssignable to boolean.
declare function acceptingBoolean(a: boolean);
>acceptingBoolean : (a: boolean) => any
>a : boolean

acceptingBoolean(isA(a));
>acceptingBoolean(isA(a)) : any
>acceptingBoolean : (a: boolean) => any
>isA(a) : boolean
>isA : (p1: any) => p1 is A
>a : A

// Type predicates with different parameter name.
declare function acceptingTypeGuardFunction(p1: (item) => item is A);
>acceptingTypeGuardFunction : (p1: (item: any) => item is A) => any
>p1 : (item: any) => item is A
>item : any

acceptingTypeGuardFunction(isA);
>acceptingTypeGuardFunction(isA) : any
>acceptingTypeGuardFunction : (p1: (item: any) => item is A) => any
>isA : (p1: any) => p1 is A

// Binary expressions
let union2: C | B;
>union2 : B | C

let union3: boolean | B = isA(union2) || union2;
>union3 : boolean | B
>isA(union2) || union2 : true | B
>isA(union2) : boolean
>isA : (p1: any) => p1 is A
>union2 : B | C
>union2 : B