Hi Yann: 

On 15 Apr 2013, at 10:41, Yann-Gaël Guéhéneuc <yann-gael.gueheneuc at polymtl.ca> wrote:

> I kind of remember that in some version/flavor of Smalltalk, you could "override" the VM mechanism to invoke method, typically by overriding some "withArgs:executeMethod:" when---and only when---using reflection so that performance would not be horrible but that you could still change the behaviour of invocations (at the risk of breaking the whole image if something silly was done, such as not "forwarding" the invocation to the VM after interception). Do I remember wrong?

Perhaps you remember reading: 'Efficient Method Lookup Customization for Smalltalk'? http://link.springer.com/chapter/10.1007/978-3-642-30561-0_10

There is also PHANtom (http://pleiad.cl/research/software/phantom)
and AspectS that might be more high-level. 

Best regards
Stefan

-- 
Stefan Marr
Software Languages Lab
Vrije Universiteit Brussel
Pleinlaan 2 / B-1050 Brussels / Belgium
http://soft.vub.ac.be/~smarr
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