Mac Hyp: Using HyperCard Global Variables for Error Checking (59977)

SUMMARY

The Microsoft Mail Software Development Kit (SDK) for HyperCard uses two HyperCard global variables to report the results of the msmail external function call. These variables are as follows: The HyperCard global mailResult holds a number that is the return code of the last call made to msmail. This is zero if the call succeeded. If an error occurred, the HyperCard global mailResultText contains a textual description of the error. If no error has occurred, mailResultText contains "No Error."

Global variables are used by declaring them as globals in the script with the Global command. For example:

   on mouseup
      global mailResult, mailResultText
      put msmail(CreateMessage) into msref
      if mailresult <> 0 then
         answer "Error: " & mailResultText
         exit mouseup
      end if
      ....
				

If a call to the server is not successful, these functions are the only way to find out that there has been an error. They are very useful in debugging and in making a stack "bullet-proof" in operation.

This information is taken from the "Microsoft Mail HyperCard Interface Documentation."