[squeak-dev] Re: Halt

Bert Freudenberg bert at freudenbergs.de
Mon Aug 29 11:28:36 UTC 2011

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


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

- Bert -

More information about the Squeak-dev mailing list