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catch

try {
    Statements;
}
catch( exception ) {
    ExceptionStatements;
}

This keyword is used in try statements. If an exception occurs, then the ExceptionStatements in a matching catch block are executed.

Catch blocks come in two varieties, unqualified and qualified. An unqualified catch block has the form:

    catch ( e ) {
        /* statements */
    }

and a qualified catch block has the form:

    catch ( e if e instanceOf RangeError ) {
        /* statements */
    }

The possible exception types are:

• EvalError -- the result of a failed eval() call.

• RangeError -- a result that is out of range, e.g. an array index to an element that isn't in the array.

• TypeError -- an attempt to perform an operation on an object of an inappropriate type.

• User defined exceptions -- exceptions that are objects of a user-defined type.

See try for an example.

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