Extending JS Error object

exception.js

/**
 * Exception thrown if an error which can only be found on runtime occurs.
 */
var RuntimeError = function(message) {
    Error.call(this);
    this.type = "RuntimeError";
    this.message = message || this.type;
};

/**
 * Exception that represents error in the program logic.
 * This kind of exceptions should directly lead to a fix in your code.
 */
var LogicError = function(message) {
    Error.call(this);
    this.type = "LogicError";
    this.message = message || this.type;
};

Sys.inherits(RuntimeError, Error);
Sys.inherits(LogicError, Error);

/**
 * Native Error types list:
 *  - EvalError: An error in the eval() function has occurred
 *  - RangeError: Out of range number value has occurred
 *  - ReferenceError: An illegal reference has occurred
 *  - SyntaxError: A syntax error within code inside the eval() function has occurred.
 *                 All other syntax errors are not caught by try/catch/finally, and will
 *                 trigger the default engine error message associated with the error.
 *                 To catch actual syntax errors, you may use the onerror event.
 *  - TypeError: An error in the expected variable type has occurred
 *  - URIError: An error when encoding or decoding the URI has occurred (ie: when calling encodeURI()).
 */
var TypeError = function(message) {
    LogicError.call(this, message);
    this.name = "TypeError";
};

/**
 * Extending Error for our own custom error types
 */
var InvalidArgumentError = function(message) {
    TypeError.call(this, message);
    this.name = "InvalidArgumentError";
};

var IOError = function(message) {
    RuntimeError.call(this, message);
    this.name = "IOError";
};

var BoundsError = function(message) {
    RuntimeError.call(this, message);
    this.name = "BoundsError";
};