Printing shortest decimal form of floating point number with Mir

[John Colvin]

On Monday, 4 January 2021 at 09:21:02 UTC, Ola Fosheim Grøstad 
wrote:
> On Monday, 4 January 2021 at 09:18:50 UTC, Ola Fosheim Grøstad 
> wrote:
>> On Monday, 4 January 2021 at 05:55:37 UTC, Ola Fosheim Grostad 
>> wrote:
>>> On Monday, 4 January 2021 at 04:37:22 UTC, 9il wrote:
>>>> I suppose the answer would be that D doesn't pretend to 
>>>> support all C++ template features and the bug is not a bug 
>>>> because we live with this somehow for years.
>>>
>>> But it is a bug even if there was no C++... An alias should 
>>> work by simple substitution, if it does not, then it is no 
>>> alias...
>>
>> Here is an even simpler example that does not work:
>>
>> struct Foo(T){}
>> void foo(T)(T!int x) {}
>>
>> alias FooInt = Foo!int;
>>
>> void main() {
>>     foo(FooInt());
>> }
>
> Oh, now wait, it does:
>
> struct Foo(T){}
> void foo(alias T)(T!int x) {}
> alias FooInt = Foo!int;
>
> void main() {
>     foo(FooInt());
> }
>
> My mistake.

What's the simplest example that doesn't work and is that simple 
example just indirection through an alias or is it actually 
indirection through a template that *when instantiated* turns out 
to be just an alias?

I have a suspicion that what you're asking for here is the 
type-inference to have x-ray vision in to uninstantiated 
templates that works for a few simple cases. Am I wrong?

To be clear, a really useful special case can be really useful 
and worthwhile, but I'm not convinced this is the principled 
"type system bug" you are saying it is.