[dmd-internals] Getting the calling scope for a function (e.g. to get __FUNC__ from the caller)

[Simen Kjaeraas via dmd-internals]

On Tuesday, 5 April 2016 at 19:59:15 UTC, Jacob Carlborg wrote:
>> On 5 apr 2016, at 16:54, Simen Kjaeraas via dmd-internals 
>> <dmd-internals at puremagic.com> wrote:
>> 
>> To get to know DMD a bit more, I decided to implement 
>> __GENSYM__, as touched upon in Nordlöw's post on Units of 
>> Measurements[1].
>> 
>> My implementation uses the mangled name of the instantiation 
>> scope and an associated counter to create a unique string, and 
>> works great for template default parameters (which is where I 
>> imagine it would see use).
>> 
>> For completeness though, I wanted to make it work as a 
>> function default parameter as well. Looking at how __FILE__ 
>> and __LINE__ are implemented, they use only Loc, not Scope. Is 
>> it at all possible to get the calling scope for a function?
>
> Not sure where you’re looking but I would guess __FILE_ and 
> __LINE__ are handled here [1], where the scope is available.
>
> [1] 
> https://github.com/D-Programming-Language/dmd/blob/master/src/expression.d#L1446

Thanks! I realized I'd misunderstood how __FUNCTION__ works, 
which is the one I should have been looking at.

That takes care using __GENSYM__ in functions, and SCOPEctfe 
handles using it in module or aggregate scopes:

struct S {
     enum s = __GENSYM__;
}

So it seems to be working now. Thanks a lot!

--
   Simen