-
Notifications
You must be signed in to change notification settings - Fork 22.4k
/
index.md
80 lines (55 loc) · 2.28 KB
/
index.md
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
---
title: TypeError
slug: Web/JavaScript/Reference/Global_Objects/TypeError
page-type: javascript-class
browser-compat: javascript.builtins.TypeError
---
{{JSRef}}
The **`TypeError`** object represents an error when an operation could not be performed, typically (but not exclusively) when a value is not of the expected type.
A `TypeError` may be thrown when:
- an operand or argument passed to a function is incompatible with the type expected by that operator or function; or
- when attempting to modify a value that cannot be changed; or
- when attempting to use a value in an inappropriate way.
`TypeError` is a {{Glossary("serializable object")}}, so it can be cloned with {{domxref("structuredClone()")}} or copied between [Workers](/en-US/docs/Web/API/Worker) using {{domxref("Worker/postMessage()", "postMessage()")}}.
`TypeError` is a subclass of {{jsxref("Error")}}.
## Constructor
- {{jsxref("TypeError/TypeError", "TypeError()")}}
- : Creates a new `TypeError` object.
## Instance properties
_Also inherits instance properties from its parent {{jsxref("Error")}}_.
These properties are defined on `TypeError.prototype` and shared by all `TypeError` instances.
- {{jsxref("Object/constructor", "TypeError.prototype.constructor")}}
- : The constructor function that created the instance object. For `TypeError` instances, the initial value is the {{jsxref("TypeError/TypeError", "TypeError")}} constructor.
- {{jsxref("Error/name", "TypeError.prototype.name")}}
- : Represents the name for the type of error. For `TypeError.prototype.name`, the initial value is `"TypeError"`.
## Instance methods
_Inherits instance methods from its parent {{jsxref("Error")}}_.
## Examples
### Catching a TypeError
```js
try {
null.f();
} catch (e) {
console.log(e instanceof TypeError); // true
console.log(e.message); // "null has no properties"
console.log(e.name); // "TypeError"
console.log(e.stack); // Stack of the error
}
```
### Creating a TypeError
```js
try {
throw new TypeError("Hello");
} catch (e) {
console.log(e instanceof TypeError); // true
console.log(e.message); // "Hello"
console.log(e.name); // "TypeError"
console.log(e.stack); // Stack of the error
}
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Error")}}