Using "%s" with inputting numberic values

[pascal111]

On Sunday, 24 July 2022 at 23:48:59 UTC, Adam D Ruppe wrote:
> On Sunday, 24 July 2022 at 23:12:46 UTC, pascal111 wrote:
>> [...]
>
> The D things in std.stdio, writef and readf, use %s to just 
> mean default for the given type. Since you passed it an int, 
> the function knows it got an int (this is different than C, 
> where the function only knows the format string so it requires 
> you to get it right) and just automatically picks a default 
> representation to scan.
>
> You can writef("%s %s", "foo", 5); and it will see "foo" is a 
> string and thus do it as a regular %s then see 5 is an int and 
> since it knows, and you asked for just the default as-string 
> representation, it will convert just like %d would.

It's like an automatic figuring for the data type.