This program prints "nan" inside the out(result){}


import std.stdio: writeln;

double sqr(double x)
    out(result) {
        writeln("result1: ", result); // prints: result1: nan
        //assert(result >= 0);
    }
    body {
        return x * x;
    }
    
void main() {
    writeln("result2: ", sqr(100)); // prints: result2: 10000
}