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Exception Handling

The throw method​

You can use the throw method to throw an exception.

rcaron
throw #System.Exception:new('funny');
// also
throw(#System.Exception:new('funny'));
rcaron
throw #System.Exception:new('funny');
// also
throw(#System.Exception:new('funny'));

The try block​

The try block runs a code block that might throw an exception safely.

rcaron
try {
    throw #System.Exception:new('funny');
}
print 'did not exit';
// Output: did not exit
rcaron
try {
    throw #System.Exception:new('funny');
}
print 'did not exit';
// Output: did not exit

The catch block​

The try block can optionally be provided with the catch block. The catch block will be executed if an exception is thrown with the exception in the exception variable.

rcaron
try {
    throw #System.Exception:new('funny');
}
catch {
    print $exception.Message;
}
// Output: funny
rcaron
try {
    throw #System.Exception:new('funny');
}
catch {
    print $exception.Message;
}
// Output: funny

The finally block​

The try block can be optionally provided with the finally block. The finally block will execute always after the try block and the catch block. If there is no catch block then the exception is thrown just like in C#.

rcaron
try {
    throw #System.Exception:new('funny');
}
catch {
    print 'catch';
}
finally {
    print 'finally';
}
// Output:
// catch
// finally
try {
    throw #System.Exception:new('funny');
}
finally {
    print 'finally';
}
// Output: finally
// System.Exception: funny
rcaron
try {
    throw #System.Exception:new('funny');
}
catch {
    print 'catch';
}
finally {
    print 'finally';
}
// Output:
// catch
// finally
try {
    throw #System.Exception:new('funny');
}
finally {
    print 'finally';
}
// Output: finally
// System.Exception: funny