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  4. [ dw::Runtime ](dw-runtime)
  5. fail 

#  fail

##  fail(message: String = 'Error'): Nothing

Throws an exception with the specified message.

###  Parameters

Name  |  Description   
---|---  
` message ` |  An error message ( ` String ` ).   
  
###  Example

This example returns a failure message ` Data was empty ` because the
expression ` (sizeOf(myVar) <= 0) ` is ` true ` . A shortened version of the
error message is shown in the output.

####  Source

    
    
    %dw 2.0
    import * from dw::Runtime
    var result = []
    output application/json
    ---
    if(sizeOf(result) <= 0) fail('Data was empty') else result

####  Output

    
    
    ERROR 2018-07-29 11:47:44,983 ...
    *********************************
    Message               : "Data was empty
    ...

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