Added some const

easywsclient.hpp

@@ -19,29 +19,29 @@ class WebSocket {
 
     // Factories:
     static pointer create_dummy();
-    static pointer from_url(std::string url);
-    static pointer from_url_no_mask(std::string url);
+    static pointer from_url(const std::string& url);
+    static pointer from_url_no_mask(const std::string& url);
 
     // Interfaces:
     virtual ~WebSocket() { }
     virtual void poll(int timeout = 0) = 0; // timeout in milliseconds
-    virtual void send(std::string message) = 0;
+    virtual void send(const std::string& message) = 0;
     virtual void close() = 0;
-    virtual readyStateValues getReadyState() = 0;
+    virtual readyStateValues getReadyState() const = 0;
     template<class Callable>
     void dispatch(Callable callable) { // N.B. this is compatible with both C++11 lambdas, functors and C function pointers
         struct _Callback : public Callback {
-            Callable & callable;
-            _Callback(Callable & callable) : callable(callable) { }
-            void operator()(const std::string & message) { callable(message); }
+            Callable& callable;
+            _Callback(Callable& callable) : callable(callable) { }
+            void operator()(const std::string& message) { callable(message); }
         };
         _Callback callback(callable);
         _dispatch(callback);
     }
 
   protected:
-    struct Callback { virtual void operator()(const std::string & message) = 0; };
-    virtual void _dispatch(Callback & callable) = 0;
+    struct Callback { virtual void operator()(const std::string& message) = 0; };
+    virtual void _dispatch(Callback& callable) = 0;
 };
 
 } // namespace easywsclient