Passing variadic template parameters AND default call site __FILE__, __LINE__ template parameters.

[realhet]

On Tuesday, 27 May 2025 at 15:01:38 UTC, monkyyy wrote:
> On Tuesday, 27 May 2025 at 10:20:40 UTC, realhet wrote:

Hi and thanks for trying!


t2!(x)  //The problem with this is the __LINE__ will point to the 
alias declaration, not the pragma.

Interesting trick: template nested inside a template.


T3!(x)   //This works perfectly, but the 8 alias has a really low 
limit on the contents of the IES string: 3 $() blocks and it's 
out of parameters.  Maybe if I generate this template with a 
string mixin, but I'm affraid the compiler would go crazy.  I'm 
planning to use it with 1000 lines of shader code and lots of 
constanst injected into that with $().

Interesting tricks: alias reassignment and 
templateParameterValueSpecialization (wow! It avoids the 
redeclaration error I normally get.).


T4!(pack!(x))  //Unlike T3, it has no limitations but it needs an 
extra work at the call site.  The simplest extra work is manually 
writing __FILE__,__LINE__ btw.

Interesting trick:  How to pack a whole AliasSeq into a single 
slot.  I got to rememper this, it's so cool.   template 
pack(A...) { alias unpack=A; }


Final thoughts: I think the only conflict is on the language 
level, as the data form __FILE__ and __LINE__ are always 
accessible inside the compiler.  But maybe in the future there 
will be a __traits for this.  And also for __COLUMN__.  But I 
also understand that these simple looking things are super 
complicated inside the compiler.

Thx for the template tricks!