Added an operator != to the file and directory objects.

dlib/dir_nav/dir_nav_kernel_1.h

@@ -148,6 +148,10 @@ namespace dlib
             const file& rhs
         ) const;
 
+        bool operator != (
+            const file& rhs
+        ) const { return !(*this == rhs); }
+
         inline bool operator < (
             const file& item
         ) const { return full_name() < item.full_name(); }
@@ -311,6 +315,10 @@ namespace dlib
             const directory& rhs
         ) const;
 
+        bool operator != (
+            const directory& rhs
+        ) const { return !(*this == rhs); }
+
         inline bool operator < (
             const directory& item
         ) const { return full_name() < item.full_name(); }

dlib/dir_nav/dir_nav_kernel_2.h

@@ -153,6 +153,10 @@ namespace dlib
             const file& rhs
         ) const;
 
+        bool operator != (
+            const file& rhs
+        ) const { return !(*this == rhs); }
+
         inline bool operator < (
             const file& item
         ) const { return full_name() < item.full_name(); }
@@ -304,6 +308,10 @@ namespace dlib
             const directory& rhs
         ) const;
 
+        bool operator != (
+            const directory& rhs
+        ) const { return !(*this == rhs); }
+
         inline bool operator < (
             const directory& item
         ) const { return full_name() < item.full_name(); }

dlib/dir_nav/dir_nav_kernel_abstract.h

@@ -162,6 +162,17 @@ namespace dlib
                     - returns false
         !*/
 
+        bool operator != (
+            const file& rhs
+        ) const;
+        /*!
+            ensures
+                - if (*this and rhs represent the same file) then
+                    - returns false 
+                - else
+                    - returns true 
+        !*/
+
         bool operator < (
             const file& item
         ) const;
@@ -392,6 +403,17 @@ namespace dlib
                     - returns false
         !*/
 
+        bool operator != (
+            const directory& rhs
+        ) const;
+        /*!
+            ensures
+                - if (*this and rhs represent the same directory) then
+                    - returns false 
+                - else
+                    - returns true 
+        !*/
+
         bool operator < (
             const directory& item
         ) const;