The JS7 - Try / Catch Instruction is used for the error handling in a workflow. If any job runs in the try block and failed due to any reason the catch block will execute otherwise it will skip the catch block. If the catch block will also fail then the order will be considered as failed. The folder 04_ErrorHandling contains the example for the try-catch. The four workflows are available with the different use cases for the try-catch:
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