Changeset 570

Timestamp:

08/20/09 08:57:55 (15 years ago)

Author:

vbarta

Message:

supporting shared_ptr<const T>

Location:

library

Files:

• bdm/shared_ptr.h (modified) (1 diff)
• tests/shared_ptr_test.cpp (modified) (2 diffs)

library/bdm/shared_ptr.h

@@ -183 +183 @@
 
         /*!
+          \brief const cast
+
+          Shared pointer to T can be converted to shared pointer to
+          const T, just like T * can be converted to T const *.
+        */
+        template<typename U>
+        operator shared_ptr<const U>() const {
+                shared_ptr<const U> cptr;               
+                cptr.refCnt = refCnt;
+                cptr.payload = payload;
+                add_ref();
+                return cptr;
+        }
+
+        /*!
           \brief Efficient swap for shared_ptr.
          */

library/tests/shared_ptr_test.cpp

@@ -21 +21 @@
 
 typedef std::vector<bdm::shared_ptr<Foo> > TFooVector;
+
+typedef std::vector<bdm::shared_ptr<const Foo> > TConstFooVector;
 
 TEST ( test_shared_ptr ) {
@@ -53 +55 @@
 }
 
+TEST ( test_shared_ptr_const ) {
+        TConstFooVector v;
+
+        bdm::shared_ptr<const Foo> zero;
+        CHECK_EQUAL ( 0l, zero.use_count() );
+        bdm::shared_ptr<const Foo> z2 ( zero );
+        CHECK_EQUAL ( 0l, z2.use_count() );
+
+        bdm::shared_ptr<const Foo> one ( new Foo ( 1 ) );
+        v.push_back ( one );
+        CHECK ( !one.unique() );
+
+        v.push_back ( one );
+        v.push_back ( bdm::shared_ptr<const Foo> ( new Foo ( 2 ) ) );
+        CHECK_EQUAL ( static_cast<TConstFooVector::size_type> ( 3 ), v.size() );
+
+        CHECK ( v[0] == v[1] );
+        CHECK ( v[1] != v[2] );
+
+        Foo c ( * ( v[0] ) );
+        CHECK_EQUAL ( 1, c.get_x() );
+
+        const Foo *p = v[1].get();
+        CHECK_EQUAL ( 1, p->get_x() );
+
+        CHECK ( v[2].unique() );
+        CHECK_EQUAL ( 2, v[2]->get_x() );
+
+        bdm::shared_ptr<Foo> non_const;
+        bdm::shared_ptr<const Foo> another ( non_const );
+        CHECK ( !non_const.unique() );
+}
+
 TEST ( test_shared_ptr_error ) {
         bdm::shared_ptr<Foo> empty;