ERROR$ generated a dialog to present an error with a possibility to terminate the process hereafter

Syntax

ERROR$(Document$, Error$, Caption$, Mode)

Arguments 

• Document$ is a string value to be returned by this function as result (could be an error message)
• Error$ is the error string which will raise an error that gracefully terminates the session if the value is not PENDING and Error$ is not "NullString". This string only controls the error trapping (and can be different from Document$)
• Caption$ is the title/description of the error that is raised
•  Mode is an optional parameter to influence the type of buttons presented with the dialog<

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1. The INCASE function is a convenient function to use in combination with the ERROR$ function. The INCASE can be used to define Error$define Error$, either to be "NullString" or have a message depending on another value or parameter.
2. Mode's 2 or 4 will be the most useful options because these buttons most clearly provide a indication of what will happen.

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In the example below, the value of Error$ is generated by an INCASE() function interpreting the output of a program named ProgX.

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