Re: Exception handling

From: [at]} <Rene>
Date: Wed, 15 Sep 2004 17:29:50 +0200

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>
>Programming in SCL convinced me that it was unwise for the procedure
>itself to decide that something is an error. Instead, it should always
>pass a result code back up the line, and everything further up the
>line should make up its own mind what to do about it - usually pass it
>further up the line. The WHENEVER clause made that very easy because
>you could just break right out.
>
>
Maybe I did not understand what you were saying, but I think of two
ways currently used by the BB to do such a thing:

1. If you have a procedure, make it a "function", returning an integer
as a return code. That way, the caller may decide how to react to a
"grey" error.
2. Where you already return something valueable, have a VAR-parameter
with the return code. If you must not complete your action due to the
nature of the error, fill the variable, and then RETURN.

Rene
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Received on Wed Sep 15 2004 - 17:29:50 UTC