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ReferenceError
Baseline
Widely available
*
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
* Some parts of this feature may have varying levels of support.
The ReferenceError object represents an error when a variable that doesn't exist (or hasn't yet been initialized) in the current scope is referenced.
ReferenceError is a serializable object, so it can be cloned with structuredClone() or copied between Workers using postMessage().
ReferenceError is a subclass of Error.
Also inherits instance properties from its parent Error.
These properties are defined on ReferenceError.prototype and shared by all ReferenceError instances.
ReferenceError.prototype.constructor-
The constructor function that created the instance object. For ReferenceError instances, the initial value is the ReferenceError constructor.
ReferenceError.prototype.name-
Represents the name for the type of error. For ReferenceError.prototype.name, the initial value is "ReferenceError".
Inherits instance methods from its parent Error.
js
try {
let a = undefinedVariable;
} catch (e) {
console.log(e instanceof ReferenceError); // true
console.log(e.message); // "undefinedVariable is not defined"
console.log(e.name); // "ReferenceError"
console.log(e.stack); // Stack of the error
}
js
try {
throw new ReferenceError("Hello");
} catch (e) {
console.log(e instanceof ReferenceError); // true
console.log(e.message); // "Hello"
console.log(e.name); // "ReferenceError"
console.log(e.stack); // Stack of the error
}