Semantics of shared

[Walter Bright]

Robert Jacques wrote:
>>>  Sorry for the confusion of terminology. However, you talk blog about 
>>> using the 'scope' keyword to support escape analysis, ettc. i.e. 
>>> 'scope' would become the 'const' of the shared-thread local-stack 
>>> storage type system. Is this still the plan?
>>
>> I'm not sure what you mean by that.
> 
> I'm asking about the use of scope you blogged about:
> 
> http://dobbscodetalk.com/index.php?option=com_myblog&show=Escape-Analysis.html&Itemid=29 
> 
> 
> [...]
> 
> For D, we are looking at a design that creates a parameter storage class 
> called scope:
> 
> T foo(scope int* p);
> 
> The presence of scope means that the function will not allow the 
> parameter, or anything reachable through that parameter, to escape from 
> the scope of the function. The scope storage class can be applied to the 
> parameters or the 'this' reference (for member functions). Initially, 
> this will be a promise by the implementor of foo(), but it should be 
> entirely possible for the compiler to perform escape analysis using data 
> flow analysis techniques on the implementation of foo() to ensure it. 
> The caller of the function will know that a reference to a local 
> variable can be safely passed as a scope parameter. A million line 
> program can be automatically verified as being free of escaping 
> reference bugs.

We've talked about it, but am unsure as to whether it will work or not.