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    TypeError

    Summary

    The TypeError object represents an error when a value is not of the expected type.

    Syntax

    new TypeError([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

    Description

    A TypeError is thrown when an operand or argument passed to a function is incompatible with the type expected by that operator or function.

    Properties

    TypeError.prototype
    Allows the addition of properties to a TypeError object.

    Methods

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

    TypeError instances

    Properties

    TypeError.prototype.constructor
    Specifies the function that created an instance's prototype.
    TypeError.prototype.message
    Error message. Although ECMA-262 specifies that TypeError should provide its own message property, in SpiderMonkey, it inherits Error.prototype.message.
    TypeError.prototype.name
    Error name. Inherited from Error.
    TypeError.prototype.fileName
    Path to file that raised this error. Inherited from Error.
    TypeError.prototype.lineNumber
    Line number in file that raised this error. Inherited from Error.
    TypeError.prototype.columnNumber
    Column number in line that raised this error. Inherited from Error.
    TypeError.prototype.stack
    Stack trace. Inherited from Error.

    Methods

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

    Examples

    Example: Catch an TypeError

    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.fileName);             // "Scratchpad/1"
      console.log(e.lineNumber);           // 2
      console.log(e.columnNumber);         // 2
      console.log(e.stack);                // "@Scratchpad/2:2:3\n"
    }
    

    Example: Create an TypeError

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

    Specifications

    Specification Status Comment
    ECMAScript 3rd Edition. Standard Initial definition.
    ECMAScript 5.1 (ECMA-262)
    The definition of 'TypeError' in that specification.
    Standard  
    ECMAScript 6 (ECMA-262)
    The definition of 'TypeError' in that specification.
    Release Candidate  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

    See also

    Document Tags and Contributors

    Contributors to this page: Sheppy, fscholz, Mingun, Sevenspade, arai, Potappo, Ward
    Last updated by: Ward,