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Decrement Counter If Wrong Keyword

<DecrementIfWrong designator>
<deciw designator>

counter designators:

    Subtracts one from counter .name. or number N if the RT is wrong. In keeping with the precedent set by early branching code wrong responses include no responses, if you need to differentiate between the two you'll have to test for the lastRT token being equal to the the timeout (so <bi 999, lastRT .eq. 4000> for instance) or use <incinr> in the next item (as you can only have one conditional operation per item per counter).  Conditional arithmetic keywords (<incic>, <inciw>, <incinr>, <decic>, <deciw> or <decinr>)  are evaluated after the item is displayed.  See the Set Counter keyword.

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