quiet some issues with Windows build

Author: kthohr

.appveyor.yml

@@ -53,3 +53,4 @@ build_script:
   - .\sqrt.test
   - .\tan.test
   - .\tanh.test
+  - ls -al

include/gcem_incl/binomial_coef.hpp

@@ -57,7 +57,7 @@ binomial_coef(const pT n, const pT k)
         // if
             internal::binomial_coef_recur<pT,eT>(n,k) :
         // else
-            internal::binomial_coef_recur<ullint_t,ullint_t>(n,k) );
+            internal::binomial_coef_recur<ullint_t,ullint_t>(static_cast<ullint_t>(n),static_cast<ullint_t>(k)) );
 }
 
 #endif

include/gcem_incl/factorial.hpp

@@ -49,10 +49,10 @@ factorial_table(const T x)
                          T(20922789888000) );
 }
 
-template<typename T>
+template<typename T, typename std::enable_if<std::is_integral<T>::value>::type* = nullptr>
 constexpr
 T
-factorial_integer(const T x)
+factorial_recur(const T x)
 {
     return( x == T(0) ? T(1) :
             x == T(1) ? x :
@@ -61,7 +61,15 @@ factorial_integer(const T x)
                 // if
                 factorial_table(x) :
                 // else
-                x*factorial_integer(x-1) );
+                x*factorial_recur(x-1) );
+}
+
+template<typename T, typename std::enable_if<!std::is_integral<T>::value>::type* = nullptr>
+constexpr
+T
+factorial_recur(const T x)
+{
+    return tgamma(x + 1);
 }
 
 }
@@ -80,11 +88,7 @@ constexpr
 T
 factorial(const T x)
 {
-    return( std::is_integral<T>::value ? \
-            // if
-                internal::factorial_integer(x) :
-            // else
-                tgamma(x + 1) );
+    return internal::factorial_recur(x);
 }
 
 #endif