On 29.08.2011, at 18:14, DeNigris Sean wrote:

> What is the purpose of #haltIf: aBlock?
> 
> Right now, you can pass any of the following to Object>>haltIf:
>  - aBlock taking an optional argument which is automatically set to the 
> receiver of #halt
>  - aSelector which looks up the call chain and halts if present
>  - aBoolean
> 
> So, whatever the condition is, it seems like you should be able to evaluate 
> it in the calling context. When would you ever need to use a block? Can we 
> eliminate the block behavior? Or, who has a great war story about blocks 
> saving them from imminent doom...

It's useful for testing an intermediate result, without having to declare 
another temp. E.g.:

        ^ foo bar + fum

becomes

        ^ (foo bar haltIf: [:x | x > 42]) + fum

- Bert -


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