Struct with default ctor (Was: [dmd-beta] dmd 2.064 beta take 2)

[deadalnix]

On Sunday, 19 May 2013 at 04:57:15 UTC, Walter Bright wrote:
> On 5/18/2013 8:54 PM, deadalnix wrote:
>> On Sunday, 19 May 2013 at 01:20:31 UTC, Walter Bright wrote:
>>> I understand that. But the rationale you gave for having a 
>>> default constructor
>>> was to be able to disable default construction.
>>
>> RAII or construction based on template parameters.
>
> I know what default constructors are used for in C++. That 
> wasn't what I asked, though. I asked for compelling rationale.
>

I have bunch of code that goes like :

auto oldVar = var;
scope(exit) var = oldVar;

This is begging for a RAII solution where I pass var as template 
parameter but would require default constructor. This is an 
actual problem I have right now as all save/restore are harder 
and harder to keep in sync for no reason and generate a lot of 
boilerplate.

This is a problem I have right now that default constructor would 
solve, and this isn't the first time I hit that need.