Unofficial wish list status.(Nov 2008)

[Frits van Bommel]

Andrei Alexandrescu wrote:
> I've been thinking of defining a simple function that binds to variable 
> addresses and allows assignment from a tuple, in which case the code 
> would be:
> 
> group(&code, &msg) = getError;
> 
> In "the future" we'll have variadic ref arguments, in which case the 
> "&"s can be dropped:
> 
> group(code, msg) = getError;

I've managed to make this work right now:
	group!(code, msg) = getError();

as well as (with a different function):
	group_!(code, msg) = getError();
	auto myGroup = group_!(code, msg);
	myGroup = getError();
(The second example has several implementations in fact. Unfortunately, 
all of them currently allocate a closure for the variables if they're 
local. The first one doesn't have that problem)

All of this is D2+Phobos, by the way. Though something similar could 
likely be made in D1 (minus the closure issues, obviously).


Unfortunately it does have a severe limitation: it only works on 
straight variables because it uses alias template parameters.
You can't assign to *b or foo.a, for instance (unless it's static).

See attachment for code.
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