On 9/14/2016 7:25 PM, Mathieu Rochette wrote: > yeah the example is not that great, I'll usually want to clone to > avoid calling a constructor with to many parameters (or a constructor > doing too many things not needed here) >
That's exactly the reason why we want the _clone_ modifier. :) On 9/14/2016 7:25 PM, Mathieu Rochette wrote: > what's the difference between the two for an immutable class? > The difference is that the engine cannot reason whether you need a clone now or not. Allowing cloning in any context directly results in the fact that someone from the outside can receive a copy of the object that is actually mutable. However, exactly that is what we want to avoid by all means. It's true that userland deep cloning implementations will need to check whether the instance at hand is cloneable or not. But as a matter of fact they need to do that already anyways because there is no guarantee that an object is actually cloneable because the `__clone` callback could be invisible (`protected`/`private`) already. -- Richard "Fleshgrinder" Fussenegger
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