[squeak-dev] How to really make portion of code optional

On Aug 16, 2008, at 1:57 PM, cdrick wrote:

> Hi,
>
> I'm looking for a way to hide/show portion of code depending on if  
> it's in development or production mode.

One approach would be to use the class hierarchy to do this. In your  
abstract superclass put the shared behavior and in the subclasses put  
the unique behavior. Then instantiate one or the other depending on  
whether you are in development or in production.

> First idea is to wrap the code in question around a global  
> productionMode var. But I was wondering if there is a better way.  
> Somethink to really hide these portions of code for efficiency.

The last thing I'd worry about is efficiency. How many times do you  
think you would execute the conditional? The thing you ought to worry  
about is making the code easy to understand and maintain. The subclass  
approach would mean that the conditional would be executed only once  
(when you instantiate the object) and the remaining code would be clear.

> I know this is not a big deal (for my project) but I'm quite sure  
> something may exist maybe at the VM level, so ...

That would be an unusual approach.

> Thanks in advance,
>
> Cédrick

James Fster

Thanks James and Laurent,

Actually this question was more to learn is it was possible. I
remember a post about keeping or not comment in the source code...

To be more precise, it's for log output of the inference system
(http://nars.seasidehosting.st/). In each step, there can be something
like 10 lines processes depending on entities are infered. The thing
is this log output chunks are mixed in the code in several places. I
could maybe use a better trigger mechanism like sending a signal with
the entity in question, but still, there will be this message sent (or
the test). I used stream and it seems ok (regarding performance), just
wanted to know if we could deactivate some portion of code as
everything seems possible here ;). I'll remind the subclass tip
though.

Cheers,

Cédrick

2008/8/17 laurent laffont <[hidden email]>:

> Otherwise Keith Hodges has a logging framework, or you could use
> Toothpick (http://www.metaprog.com/Toothpick/) which I believe has a
> Smalltalk implementation.
>
> Gulik.
FYI:

The 'Logging' framework serves as a standard interface to a number of
backends of which there are 5.

Null - Null Logger does nothing.
TranscriptLog - Logs thread safely to the Transcript (part of standard
Logging package)
SimpleLog - Adaptor onto the SLLog code from Gjallar, includes:
    - startMorph
    - startFile: filename
    - startSyslog
    - startTranscript
Toothpick - Adaptor onto the toothpick framework
LogEngine - Adaptor onto the LogEngine code (not yet implemented)

best regards

Keith