Errors 101

sqlRecvTask>>raiseError: aSymbol 
    "a recv_ack_rpprebok is special it does not 
    return result sets thus no data back to IMS. Also don't allow a bad txn message to 
    cause a restart, trap it here" 

    (aSymbol == #badAnswer 
        and: [(self sqlPeek copyFrom: 1 to: 22) = 'exec recv_ack_rpprebok']) ifTrue: [^self].
    aSymbol == #recvBadTxn ifTrue: 
        [self errorlogIt: BadTxn. 
        ^self]. 
    super raiseError: aSymbol. 

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Notes:

In a few cases I found myself needing to signal an exception, but perhaps not a fatal error. To solve this, I coded a raiseError: method where you supply a symbol as reference data. In various places I raised errors. Later we revisited situations like the one above, and decided what could be handled, versus using the symbol to log more information and abort the session

In my opinion, using exception handlers is more difficult. From a maintenance perspective, it's an 'advanced topic' for junior Smalltalkers to grasp.

But that doesn't preclude its usage for advanced programmers.