[OT] new thing I learned for today

[Steven Schveighoffer]

On 12/18/19 9:18 AM, jmh530 wrote:
> On Wednesday, 18 December 2019 at 01:20:33 UTC, Steven Schveighoffer wrote:
>> [snip]
>>
>> BTW, people have been talking about usage like:
>>
>> auto str = i"I have $apples apples".format;
>>
>> And it got me thinking, does this actually work? I mean, can multiple 
>> parameters be used for UFCS?
>>
>> Answer: yes.
>>
>> auto str = AliasSeq!("I have %s apples", apples).format; // OK
>>
>> pretty cool. I had no idea.
>>
> 
> I think it works because format takes a variadic template as an input. 
> Given the connection between variadic templates and AliasSeq, the input 
> is basically an AliasSeq in the first place. Shouldn't be an issue 
> having AliasSeq's with length>1.
> 
> I don't know if I would describe it as multiple parameters. I would call 
> UFCS with multiple parameters as describing when you have foo(x, y, z), 
> you can call x.foo(y, z). In this case, something like
> auto str = AliasSeq!("I have %s apples").format(apples);
> also compiles without error and would be more comparable.

Nope. Not just variadic templates:

assert(AliasSeq!(2, 2).pow == 4);

Not even templates in general:

int foo(int x, int y) { return x + y; }

assert(AliasSeq!(1, 2).foo == 3);

-Steve