Templates do maybe not need to be that slow (no promises)

[Stefan Koch via Digitalmars-d]

Hi Guys,

I keep this short.
There seems to be much more headroom then I had thought.

The Idea is pretty simple.

Consider :
int fn(int padLength)(int a, int b, int c)
{
   /**
    very long function body 1000+ lines
    */
   return result * padLength;
}

This will produce roughly the same code for every instaniation 
expect for one imul at the end.

This problem is known as template bloat.


There is a direct linear relationship between the generated code 
and  the template body.
So If the range of change inside the template body can be linked 
to the changed range in the binray and we link this to the 
template parameters we can produce a pure function that can give 
us the change in the binary code when provided with the template 
parameters.
And the need to rerun the instanciation and code-gen is reduced 
to just the changed sections.

I am not yet sure if this is viable to implement.