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//// [typeGuardsDefeat.ts]
// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x: number | string) {
function f() {
x = 10;
}
if (typeof x === "string") {
f();
return x.length; // string
}
else {
return x++; // number
}
}
function foo2(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
var f = function () {
return x * x;
};
}
x = "hello";
f();
}
function foo3(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
var f = () => x * x;
}
x = "hello";
f();
}
//// [typeGuardsDefeat.js]
// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x) {
function f() {
x = 10;
}
if (typeof x === "string") {
f();
return x.length; // string
}
else {
return x++; // number
}
}
function foo2(x) {
if (typeof x === "string") {
return x.length; // string
}
else {
var f = function () {
return x * x;
};
}
x = "hello";
f();
}
function foo3(x) {
if (typeof x === "string") {
return x.length; // string
}
else {
var f = function () { return x * x; };
}
x = "hello";
f();
}
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