WebAssembly.RuntimeError

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since October 2017.

The WebAssembly.RuntimeError object is the error type that is thrown whenever WebAssembly specifies a trap.

Constructor

WebAssembly.RuntimeError()

Creates a new WebAssembly.RuntimeError object.

Instance properties

WebAssembly.RuntimeError.prototype.message

Error message. Inherited from Error.

WebAssembly.RuntimeError.prototype.name

Error name. Inherited from Error.

WebAssembly.RuntimeError.prototype.cause

Error cause. Inherited from Error.

WebAssembly.RuntimeError.prototype.fileName Non-standard

Path to file that raised this error. Inherited from Error.

WebAssembly.RuntimeError.prototype.lineNumber Non-standard

Line number in file that raised this error. Inherited from Error.

WebAssembly.RuntimeError.prototype.columnNumber Non-standard

Column number in line that raised this error. Inherited from Error.

WebAssembly.RuntimeError.prototype.stack Non-standard

Stack trace. Inherited from Error.

Instance methods

WebAssembly.RuntimeError.prototype.toString()

Returns a string representing the specified Error object. Inherited from Error.

Examples

Creating a new RuntimeError instance

The following snippet creates a new RuntimeError instance, and logs its details to the console:

js
try {
  throw new WebAssembly.RuntimeError("Hello", "someFile", 10);
} catch (e) {
  console.log(e instanceof WebAssembly.RuntimeError); // true
  console.log(e.message); // "Hello"
  console.log(e.name); // "RuntimeError"
  console.log(e.fileName); // "someFile"
  console.log(e.lineNumber); // 10
  console.log(e.columnNumber); // 0
  console.log(e.stack); // returns the location where the code was run
}

Specifications

Specification
WebAssembly JavaScript Interface
# exceptiondef-runtimeerror
ECMAScript® 2025 Language Specification
# sec-native-error-types-used-in-this-standard

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
RuntimeError
RuntimeError() constructor

Legend

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Full support
Full support

See also