From 6a81ba6b23cace55abdb32b66ea2e4a4565d051b Mon Sep 17 00:00:00 2001
From: Davis King <davis@dlib.net>
Date: Mon, 11 Jan 2010 22:15:06 +0000
Subject: [PATCH] Added missing requires clause to the get() function of the
 type_safe_union. It will now cause a compile time error if called
 inappropriately.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403382
---
 dlib/type_safe_union/type_safe_union_kernel.h | 21 ++++++++++++++++++-
 .../type_safe_union_kernel_abstract.h         |  2 ++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/dlib/type_safe_union/type_safe_union_kernel.h b/dlib/type_safe_union/type_safe_union_kernel.h
index 7c9d44733..4be70a25e 100644
--- a/dlib/type_safe_union/type_safe_union_kernel.h
+++ b/dlib/type_safe_union/type_safe_union_kernel.h
@@ -301,7 +301,26 @@ namespace dlib
             }
         }
 
-        template <typename T> T& get() { construct<T>();  return *reinterpret_cast<T*>(mem.get()); }
+        template <typename T> 
+        T& get(
+        ) 
+        { 
+            // ERROR: You are trying to get a type of object that isn't currently
+            // in the type_safe_union.
+            COMPILE_TIME_ASSERT(( is_same_type<T,T1>::value ||
+                                 is_same_type<T,T2>::value ||
+                                 is_same_type<T,T3>::value ||
+                                 is_same_type<T,T4>::value ||
+                                 is_same_type<T,T5>::value ||
+                                 is_same_type<T,T6>::value ||
+                                 is_same_type<T,T7>::value ||
+                                 is_same_type<T,T8>::value ||
+                                 is_same_type<T,T9>::value ||
+                                 is_same_type<T,T10>::value 
+                                    ));
+
+            construct<T>();  return *reinterpret_cast<T*>(mem.get()); 
+        }
 
     };
 
diff --git a/dlib/type_safe_union/type_safe_union_kernel_abstract.h b/dlib/type_safe_union/type_safe_union_kernel_abstract.h
index 7be1f62e7..bcbb45e65 100644
--- a/dlib/type_safe_union/type_safe_union_kernel_abstract.h
+++ b/dlib/type_safe_union/type_safe_union_kernel_abstract.h
@@ -120,6 +120,8 @@ namespace dlib
         T& get(
         );
         /*!
+            requires
+                - T must be one of the types given to this object's template arguments
             ensures
                 - #is_empty() == false
                 - #contains<T>() == true