reduce condition nesting

[Ali Çehreli]

On 11/25/2017 02:05 PM, Adam D. Ruppe wrote:
> On Saturday, 25 November 2017 at 21:42:29 UTC, Ali Çehreli wrote:
>> I tried to implement the following but gave up because I could not 
>> ensure short circuit behaviour.
>>
>>     when(
>>         c1.then(foo()),
>>         c2.then(bar()),
>>         otherwise(zar())
>>     );
>>
>> Possible?
> 
> Bones: "Perhaps the professor can use your computer."
> 
> https://dlang.org/spec/function.html#lazy_variadic_functions
> 
> Dr. Nichols: "Lazy variadic functions?!"
> Scotty: "That's the ticket, laddie."
> 
> ---
> import std.stdio;
> 
> void when(bool delegate()[] foo...) {
>      foreach(i; foo) {
>          if(i())
>              return;
>      }
> }

Cool! So, D is great even without templates. ;)

Despite 'lazy', apparently my failed attempt had eager arguments:

void when(lazy bool[] args...) {
     // ...
}

Ali