DIP 1027---String Interpolation---Community Review Round 1

[Jab]

On Thursday, 26 December 2019 at 15:23:07 UTC, Mike Parker wrote:
> On Thursday, 26 December 2019 at 10:20:06 UTC, Patrick Schluter 
> wrote:
>>
>>
>> If you read in the thread, Walter accepted the change to $ 
>> because od %% problem I noticed in the beginning of the thread.
>> I suppose he will amebd the document after that review cycle.
>
> He updated it last week:
>
> https://github.com/dlang/DIPs/commit/1f5959abe482b1f9094f6484a7d0a3ade77fc2fc


> No attempt is made to diagnose format specification errors, 
> such as attempting to format
an integer as a floating point value. The meaning of the format 
specifications is unknown
to the core language.

Why is this? If the language is going to embed the library 
feature of printf into the language spec, then it should know 
about and check formatting.

> string tool = "hammer";
> writefln(i"hammering %s with $tool", "nails");
> ```
> will produce:
> ```
> string tool = "hammer";
> writefln("hammering %s with %s", tool, "nails");
> ```

There's an obvious problem, even with the given example. This 
will print:

     hammering hammer with nails

Instead of the expected:

     hammering nails with hammer