Is there a way to make a function parameter accept only values that can be checked at compile time?

[rempas]

On Wednesday, 29 December 2021 at 14:49:40 UTC, Steven 
Schveighoffer wrote:
> On 12/29/21 3:55 AM, rempas wrote:
>
>> Thanks! That's cool but I don't want this to be this way. Or 
>> at least I want it to be able to take a default value so we 
>> don't have to get passed all the time.
> OK:
>
>> 
>> ```
>> extern (C) void main() {
>>    void print_num(int mul = 100)(int num) {
>>      static if (is(mul == ten)) {
>>        printf("%d\n", num * 10);
>>      } else static if (is(mul == three)) {
>>        printf("%d\n", num * 3);
>>      } else {
>>        printf("%d\n", num);
>>      }
>>    }
>> 
>>    int multi = 211;
>>    print_num!3(10);     // Set the value
>>    print_num(30);        // Get the default value, have the 
>> "else" branch executed
>> }
>> ```
>
> Template parameters are just like regular parameters, but 
> compile time.
>
> -Steve

Oh! Didn't knew you could do something like that! It works as 
expected! Thanks a lot!