DoubleFunction: safer variadic call with variadic template

latan/Function.cpp

@@ -20,24 +20,6 @@
 #include <latan/Function.hpp>
 #include <latan/includes.hpp>
 
-#define DEF_STD_FUNC_1ARG(name, funcName) \
-name##Function::name##Function(void): DoubleFunction(1) {}\
-name##Function::~name##Function(void) {}\
-double name##Function::operator()(std::vector<double> &arg)\
-{\
-    return funcName(arg[0]);\
-}\
-name##Function STDMATH_NAMESPACE::funcName;
-
-#define DEF_STD_FUNC_2ARG(name, funcName) \
-name##Function::name##Function(void): DoubleFunction(2) {}\
-name##Function::~name##Function(void) {}\
-double name##Function::operator()(std::vector<double> &arg)\
-{\
-return funcName(arg[0], arg[1]);\
-}\
-name##Function STDMATH_NAMESPACE::funcName;
-
 using namespace std;
 using namespace Latan;
 
@@ -108,20 +90,9 @@ double DoubleFunction::operator()(std::stack<double> &arg) const
     return (*this)(*buffer_);
 }
 
-double DoubleFunction::operator()(const double x0, ...) const
+double DoubleFunction::operator()(void) const
 {
-    (*buffer_)[0] = x0;
-    if (getNArg() > 1)
-    {
-        va_list va;
-        
-        va_start(va, x0);
-        for (Index i = 1; i < getNArg(); ++i)
-        {
-            (*buffer_)(i) = va_arg(va, double);
-        }
-        va_end(va);
-    }
+    checkSize(0);
     
-    return (*this)(*buffer_);
+    return (*this)(nullptr);
 }

latan/Function.hpp

@@ -48,7 +48,9 @@ public:
     double operator()(const DVec &arg) const;
     double operator()(const std::vector<double> &arg) const;
     double operator()(std::stack<double> &arg) const;
-    double operator()(const double x0, ...) const;
+    double operator()(void) const;
+    template <typename... Ts>
+    double operator()(const double arg0, const Ts... args) const;
 protected:
     // function call
     virtual double operator()(const double *arg) const;
@@ -61,6 +63,19 @@ private:
     static const vecFunc  nullFunction_;
 };
 
+template <typename... Ts>
+double DoubleFunction::operator()(const double arg0, const Ts... args) const
+{
+    static_assert(static_or<std::is_trivially_assignable<double, Ts>::value...>::value,
+                  "DoubleFunction arguments are not compatible with double");
+    
+    const double arg[] = {arg0, args...};
+    
+    checkSize(sizeof...(args) + 1);
+    
+    return (*this)(arg);
+}
+
 END_NAMESPACE
 
 #endif // Latan_Function_hpp_

latan/Global.hpp

@@ -24,6 +24,7 @@
 #include <map>
 #include <string>
 #include <sstream>
+#include <type_traits>
 #include <cstdlib>
 
 #define BEGIN_NAMESPACE namespace Latan {
@@ -33,10 +34,8 @@
 #define unique_arg(...) __VA_ARGS__
 
 // attribute to switch off unused warnings with gcc
-#ifdef __GNUC__
-#define __dumb __attribute__((unused))
-#else
-#define __dumb
+#ifndef __GNUC__
+#define __unused
 #endif
 
 // max length for paths
@@ -104,6 +103,27 @@ using ConstMap = Eigen::Map<const Derived>;
 // Index type //////////////////////////////////////////////////////////////////
 typedef DMatBase::Index Index;
 
+// Type utilities //////////////////////////////////////////////////////////////
+// pointer type test
+template <typename Derived, typename Base>
+inline bool isDerivedFrom(const Base *pt)
+{
+    return (dynamic_cast<const Derived *>(pt) != nullptr);
+}
+
+// static logical or
+template <bool... b>
+struct static_or;
+
+template <bool... tail>
+struct static_or<true, tail...> : static_or<tail...> {};
+
+template <bool... tail>
+struct static_or<false, tail...> : std::false_type {};
+
+template <>
+struct static_or<> : std::true_type {};
+
 // Environment /////////////////////////////////////////////////////////////////
 namespace Env
 {
@@ -113,14 +133,7 @@ namespace Env
     extern const std::string msgPrefix;
 }
 
-// pointer type test
-template <typename Derived, typename Base>
-inline bool isDerivedFrom(const Base *pt)
-{
-    return (dynamic_cast<const Derived *>(pt) != nullptr);
-}
-
-// string conversions //////////////////////////////////////////////////////////
+// String conversions //////////////////////////////////////////////////////////
 template <typename T>
 inline T strTo(const std::string &str)
 {