new should lower to a template function call

[Johan]

On Friday, 24 July 2020 at 18:07:21 UTC, H. S. Teoh wrote:
>
> Another problem is error messages, as someone else has already 
> pointed out.  Although we have seen improvements in 
> template-related error messages, they are still very 
> user-unfriendly, often coming in the form of indirect messages 
> like "this call does not match any of the following 25 
> overloads", and the user has to sift through pages upon pages 
> of indecipherably-long template symbols and somehow deduce that 
> what the compiler *really* want to say was "you have a typo on 
> line 123".

This we can easily test. What would it look like if there is an 
error in a user class constructor when it is called by a druntime 
function versus currently?

-Johan