CTFE fmod ?

userABCabc123 via Digitalmars-d-learn digitalmars-d-learn at puremagic.com
Fri Nov 20 03:16:11 PST 2015


Does someone have a good CTFE fmod() function ? The problem is 
that std.math.fmod() is itself not available at CT, neither do 
floor() or similar functions necessary to get the quotient when 
the input value is two times over/under the bounds.

Currently I have this one...

---
auto warp(T)(T x, T min, T max)
{
     if (x > max)
     {
         T rng = max - min;
         while (x > max + rng)
             x -= rng * 2;
         if (x > max)
             x -= rng;
     }
     else if (x < min)
     {
         T rng = max - min;
         while (x < min - rng)
             x += rng * 2;
         if (x < min)
             x += rng;
     }
     return x;
}
---

...but it fails to compile with certain float values. This 
example will consume a lot of memory ( I guess it's the while() 
loop in the CTFE VM who's responsible):

---
static assert(warp(2357136044, -5f, 5f).approxEqual(-1f));
---

Any suggestion ? Or maybe this is a limit ?



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