In the C standard library there are the sqrtf, cosf, sinf functions, that return a 32 bit float. In D std.math.sqrt returns a float if the input argument is float, but sin and cos return double even if their argument is float:

import std.math: sqrt, sin, cos;
void main() {
    float x = 1.0f;
    static assert(is(typeof(  sqrt(x)  ) == float)); // OK
    static assert(is(typeof(  sin(x)   ) == float)); // ERR
    static assert(is(typeof(  cos(x)   ) == float)); // ERR
}

I think this is not correct, and it's worth a Bugzilla entry (if not already present). Do you agree?

Bye,
bearophile

http://d.puremagic.com/issues/show_bug.cgi?id=5866