DIP 1027---String Interpolation---Format Assessment

[Walter Bright]

On 2/26/2020 10:38 PM, FeepingCreature wrote:
> On Thursday, 27 February 2020 at 03:50:35 UTC, Walter Bright wrote:
>> On 2/26/2020 4:46 PM, Adam D. Ruppe wrote:
>>> But DIP1027 had a fatal flaw: it made type safety impossible.
>>
>> I don't see how that is true.
> 
> Because it turned a format string into a list of built-in types 
> indistinguishable from a set of manual parameters. You cannot in principle tell 
> the difference between "test $i" and ("test %s", i) - you cannot write a 
> function that takes a string and then *any other type* and is also protected 
> from being accidentally called with a format string.

That isn't a type safety error.