DMD producing huge binaries

[Rene Zwanenburg via Digitalmars-d]

On Friday, 20 May 2016 at 12:08:37 UTC, ZombineDev wrote:
> @Rene
> How do you expect the compiler to know the exact return type, 
> only by looking at this signature:
> auto transmogrify(string str);
>
> A possible implementation might be this:
> auto transmogrify(string str)
> {
>    return str.map!someFunc.filter!otherFunc.joiner();
> }
>
> or something completly different.

I was thinking of something along the lines of this:

=======
size_t frobnicate(int i)
{
	return 0;
}

auto frobnicator(T)(T t)
{
	static struct Result
	{
		int index;
		
		size_t front()
		{
			return frobnicate(index);
		}
		
		enum empty = false;
		
		void popFront()
		{
			++index;
		}
	}
	
	return Result(t.index);
}
=======

Automatically generating a header with DMD gives me:

=======
size_t frobnicate(int i);
auto frobnicator(T)(T t)
{
	static struct Result
	{
		int index;
		size_t front();
		enum empty = false;
		void popFront();
	}
	return Result(t.index);
}
=======

Now frobnicator returns a different type for the same T depending 
on whether you're using the .d or the .di file. I'm not sure if 
this is a problem, but it sounds like something that can come 
back to bite you in edge cases.