[fpc-devel] Defer keyword

[Michael Van Canneyt]

On Fri, 7 May 2021, Sven Barth via fpc-devel wrote:

>
> In my opinion the better solution is to continue the road that Maciej 
> started and to implement that "default field" concept together with 
> operator hoistening so that records with management operators can be 
> used as containers. This is essentially the way it's done in C++ as well 
> (e.g. we use that extensively at work), but it needs some questions 
> solved for the default field functionality. This way the functionality 
> is definitely optional and can be controlled per-instance instead of 
> per-type. What it wouldn't solve however would be the assignment 
> problems ("wrapped" to non-"wrapped" instance) though that could be 
> probably be more or less solved by only allowing an explicit conversion 
> to the non-"wrapped" instance.

I thought it was agreed at the time that this was the most viable way
forward ?

IIRC there was also the proposal that this could be done automatically using
a keyword:

var
   SomeClass : TSomeClass; dispose;

The compiler can internally create the management record with a single default 
field and the needed management operator, so the user does not need 
to create all that.

I cannot speak for others, but I think 90% of potential use cases for ref counting
would be covered like this in my code: objects that only live inside a
procedure.

Michael.