Refactor code and declaration more local

src/SFML/Audio/SoundFileWriterFlac.cpp

@@ -39,7 +39,7 @@ namespace priv
 ////////////////////////////////////////////////////////////
 bool SoundFileWriterFlac::check(const std::string& filename)
 {
-    std::string extension = filename.substr(filename.find_last_of(".") + 1);
+    std::string extension = filename.substr(filename.find_last_of('.') + 1);
     std::transform(extension.begin(), extension.end(), extension.begin(), ::tolower);
 
     return extension == "flac";

src/SFML/Audio/SoundFileWriterOgg.cpp

@@ -40,7 +40,7 @@ namespace priv
 ////////////////////////////////////////////////////////////
 bool SoundFileWriterOgg::check(const std::string& filename)
 {
-    std::string extension = filename.substr(filename.find_last_of(".") + 1);
+    std::string extension = filename.substr(filename.find_last_of('.') + 1);
     std::transform(extension.begin(), extension.end(), extension.begin(), ::tolower);
 
     return extension == "ogg";

src/SFML/Audio/SoundFileWriterWav.cpp

@@ -77,7 +77,7 @@ namespace priv
 ////////////////////////////////////////////////////////////
 bool SoundFileWriterWav::check(const std::string& filename)
 {
-    std::string extension = filename.substr(filename.find_last_of(".") + 1);
+    std::string extension = filename.substr(filename.find_last_of('.') + 1);
     std::transform(extension.begin(), extension.end(), extension.begin(), ::tolower);
 
     return extension == "wav";

src/SFML/Network/Ftp.cpp

@@ -366,7 +366,7 @@ Ftp::Response Ftp::sendCommand(const std::string& command, const std::string& pa
 {
     // Build the command string
     std::string commandStr;
-    if (parameter != "")
+    if (!parameter.empty())
         commandStr = command + " " + parameter + "\r\n";
     else
         commandStr = command + "\r\n";

src/SFML/Network/Http.cpp

@@ -327,7 +327,7 @@ void Http::setHost(const std::string& host, unsigned short port)
     {
         // HTTPS protocol -- unsupported (requires encryption and certificates and stuff...)
         err() << "HTTPS protocol is not supported by sf::Http" << std::endl;
-        m_hostName = "";
+        m_hostName.clear();
         m_port     = 0;
     }
     else

src/SFML/Window/WindowImpl.cpp

@@ -181,7 +181,6 @@ void WindowImpl::processJoystickEvents()
         // Copy the previous state of the joystick and get the new one
         JoystickState previousState = m_joystickStates[i];
         m_joystickStates[i] = JoystickManager::getInstance().getState(i);
-        JoystickCaps caps = JoystickManager::getInstance().getCapabilities(i);
 
         // Connection state
         bool connected = m_joystickStates[i].connected;
@@ -199,6 +198,8 @@ void WindowImpl::processJoystickEvents()
 
         if (connected)
         {
+            JoystickCaps caps = JoystickManager::getInstance().getCapabilities(i);
+
             // Axes
             for (unsigned int j = 0; j < Joystick::AxisCount; ++j)
             {