SyntaxError

The SyntaxError object represents an error when trying to interpret syntactically invalid code.

Description

A SyntaxError is thrown when the JavaScript engine encounters tokens or token order that does not conform to the syntax of the language when parsing code.

Syntax

new SyntaxError([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

SyntaxError.prototype

Allows the addition of properties to a SyntaxError object.

Methods

The global SyntaxError contains no methods of its own, however, it does inherit some methods through the prototype chain.

SyntaxError instances

Properties

SyntaxError.prototype.constructor

Specifies the function that created an instance's prototype.

SyntaxError.prototype.message

Error message. Although ECMA-262 specifies that SyntaxError should provide its own message property, in SpiderMonkey, it inherits Error.prototype.message.

SyntaxError.prototype.name

Error name. Inherited from Error.

SyntaxError.prototype.fileName

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

SyntaxError.prototype.lineNumber

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

SyntaxError.prototype.columnNumber

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

SyntaxError.prototype.stack

Stack trace. Inherited from Error.

Methods

Although the SyntaxError prototype object does not contain any methods of its own, SyntaxError instances do inherit some methods through the prototype chain.

Examples

Catching a SyntaxError

try {
  eval('hoo bar');
} catch (e) {
  console.log(e instanceof SyntaxError); // true
  console.log(e.message);                // "missing ; before statement"
  console.log(e.name);                   // "SyntaxError"
  console.log(e.fileName);               // "Scratchpad/1"
  console.log(e.lineNumber);             // 1
  console.log(e.columnNumber);           // 4
  console.log(e.stack);                  // "@Scratchpad/1:2:3\n"
}

Creating a SyntaxError

try {
  throw new SyntaxError('Hello', 'someFile.js', 10);
} catch (e) {
  console.log(e instanceof SyntaxError); // true
  console.log(e.message);                // "Hello"
  console.log(e.name);                   // "SyntaxError"
  console.log(e.fileName);               // "someFile.js"
  console.log(e.lineNumber);             // 10
  console.log(e.columnNumber);           // 0
  console.log(e.stack);                  // "@Scratchpad/2:11:9\n"
}

Specifications

Browser compatibility

See also

• Error
• SyntaxError.prototype