This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The WebAssembly.RuntimeError()
constructor creates a new WebAssembly RuntimeError
object — the type that is thrown whenever WebAssembly specifies a trap.
Syntax
new WebAssembly.RuntimeError(message, fileName, lineNumber)
Parameters
message
Optional- Human-readable description of the error.
fileName
Optional- The name of the file containing the code that caused the exception.
lineNumber
Optional- The line number of the code that caused the exception.
Properties
The RuntimeError
constructor contains no unique properties of its own, however, it does inherit some properties through the prototype chain.
WebAssembly.RuntimeError.prototype.constructor
- Specifies the function that created an instance's prototype.
WebAssembly.RuntimeError.prototype.message
- Error message. Although ECMA-262 specifies that
URIError
should provide its ownmessage
property, in SpiderMonkey, it inheritsError.prototype.message
. WebAssembly.RuntimeError.prototype.name
- Error name. Inherited from
Error
. WebAssembly.RuntimeError.prototype.fileName
- Path to file that raised this error. Inherited from
Error
. WebAssembly.RuntimeError.prototype.lineNumber
- Line number in file that raised this error. Inherited from
Error
. WebAssembly.RuntimeError.prototype.columnNumber
- Column number in line that raised this error. Inherited from
Error
. WebAssembly.RuntimeError.prototype.stack
- Stack trace. Inherited from
Error
.
Methods
The RuntimeError
constructor contains no methods of its own, however, it does inherit some methods through the prototype chain.
WebAssembly.RuntimeError.prototype.toSource()
- Returns code that could eval to the same error. Inherited from
Error
. WebAssembly.RuntimeError.prototype.toString()
- Returns a string representing the specified
Error
object.. Inherited fromError
.
Examples
The following snippet creates a new RuntimeError
instance, and logs its details to the console:
try { throw new WebAssembly.RuntimeError('Hello', 'someFile', 10); } catch (e) { console.log(e instanceof 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 | Status | Comment |
---|---|---|
Web Assembly JavaScript API The definition of 'WebAssembly constructors' in that specification. |
Draft | Initial WebAssembly draft definition. |
ECMAScript Latest Draft (ECMA-262) The definition of 'NativeError' in that specification. |
Draft | Definition of standard NativeError types. |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 57 | 15[2] | 52 (52)[1] | No support | 44 | 11 |
Feature | Chrome for Android | Android Webview | Edge Mobile | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|
Basic support | 57 | 57 | No support | 52.0 (52)[1] | No support | No support | 11 |
[1] WebAssembly is enabled in Firefox 52+, although disabled in the Firefox 52 Extended Support Release (ESR.)
[2] Currently supported behind the “Experimental JavaScript Features” flag. See this blog post for more details.