Interpolated strings

[Jonas Drewsen via Digitalmars-d]

On Saturday, 15 April 2017 at 20:04:13 UTC, Jonas Drewsen wrote:
> Hi all
>
>   I've been wanting to have support for interpolated strings in 
> D for some time now that will allow you to write e.g.:
>
> auto a = 7;
> writeln( $"{a} times 3 is {a*3}" );
>
> Code speaks louder that words so I've made a PR that adds this 
> support to ddmd as a RFC [1].
>
> The compiler will basically lower the $"..." string to a mixin 
> that concatenates
> the expression parts of the (inside the {}) and the plain text 
> parts.
>
> I do recognize that this is not part of the 2017 H1 plan but I 
> also believe such smaller improvements added regularly can make 
> the language both more productive and attractive.
>
> In case this addition gets a thumbs up I will of course improve 
> test coverage and any needed quality of implementation.
>
> [1] https://github.com/dlang/dmd/pull/6703

Seems like there are mixed opinions about inclusion of a thing 
like this.

Looking at all the old PRs on dlang github slowly bit rotting it 
makes me
wonder how not to end up in that pool.

I think that history has shown that Walter/Andrei are gatekeepers 
on what
will ever get into the language. For the sake of contributers 
(incl. me or course :) ) it would make sense to get a preliminary 
"never going in" clarification by them early on. Even before a 
DIP has been written because writing that takes a good amount of 
effort.

Also collect these declined language change decisions (such as 
AST Macros) on the wiki for future contributers to scan through 
before anything else. I volunteer to add "interpolated strings" 
to the page in case it gets declined. The page could also list 
pre-approved language changes such as async functions (which 
Walter wants afaik).

I guess the main question is really to Walter and Andrei if we 
could get some kind "never going in" or "could be considered" 
clarification on e.g. news group threads named like e.g. 
"Language Design Change: Interpolated string"? Based on that the 
next steps: DIP, PR etc. step would take place.