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//// [typeGuardFunction.ts]
class A {
propA: number;
}
class B {
propB: number;
}
class C extends A {
propC: number;
}
declare function isA(p1: any): p1 is A;
declare function isB(p1: any): p1 is B;
declare function isC(p1: any): p1 is C;
declare function retC(): C;
var a: A;
var b: B;
// Basic
if (isC(a)) {
a.propC;
}
// Sub type
var subType: C;
if(isA(subType)) {
subType.propC;
}
// Union type
var union: A | B;
if(isA(union)) {
union.propA;
}
// Call signature
interface I1 {
(p1: A): p1 is C;
}
// 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;
if (isC_multipleParams(a, 0)) {
a.propC;
}
// Methods
var obj: {
func1(p1: A): p1 is C;
}
class D {
method1(p1: A): p1 is C {
return true;
}
}
// Arrow function
let f1 = (p1: A): p1 is C => false;
// Function type
declare function f2(p1: (p1: A) => p1 is C);
// Function expressions
f2(function(p1: A): p1 is C {
return true;
});
// Evaluations are asssignable to boolean.
declare function acceptingBoolean(a: boolean);
acceptingBoolean(isA(a));
// Type predicates with different parameter name.
declare function acceptingTypeGuardFunction(p1: (item) => item is A);
acceptingTypeGuardFunction(isA);
// Binary expressions
let union2: C | B;
let union3: boolean | B = isA(union2) || union2;
//// [typeGuardFunction.js]
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
var A = /** @class */ (function () {
function A() {
}
return A;
}());
var B = /** @class */ (function () {
function B() {
}
return B;
}());
var C = /** @class */ (function (_super) {
__extends(C, _super);
function C() {
return _super !== null && _super.apply(this, arguments) || this;
}
return C;
}(A));
var a;
var b;
// Basic
if (isC(a)) {
a.propC;
}
// Sub type
var subType;
if (isA(subType)) {
subType.propC;
}
// Union type
var union;
if (isA(union)) {
union.propA;
}
if (isC_multipleParams(a, 0)) {
a.propC;
}
// Methods
var obj;
var D = /** @class */ (function () {
function D() {
}
D.prototype.method1 = function (p1) {
return true;
};
return D;
}());
// Arrow function
var f1 = function (p1) { return false; };
// Function expressions
f2(function (p1) {
return true;
});
acceptingBoolean(isA(a));
acceptingTypeGuardFunction(isA);
// Binary expressions
var union2;
var union3 = isA(union2) || union2;
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