inplace opers

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@5862 626c5289-ae23-0410-ae9c-e8d60b6d4f22

CHANGES.current

@@ -1,6 +1,36 @@
 Version 1.3.22 (in progress)
 ==================================
 
+04/10/2004: mmatus (Marcelo Matus) 
+	    
+	    [python] Fix the default behaviour (seg. fault) when an
+	    inplace operator (+=,-=,...) was wrapped, as reported by
+	    Lucriz (lucriz@sitilandia.it), when the most common
+	    form was used:
+
+                   A&  A::operator+=(int i) { ...; return *this; }
+                  ^^^^                                    ^^^^^^
+	    
+
+	    ie, an object is returned and its contains the same 'this'
+	    value than the input object, which is deleted after the
+	    operation "a += b", leaving the result with no real
+	    object, but a seg. fault.
+
+	    To fix it, we needed to introduce a new feature and use an
+	    old one:
+
+               %feature("self:disown","") A::operator+=;
+               %feature("new","") A::operator+=;
+	    
+	    here, "self:disown" disable the ownership of the 'self'
+	    or input object, and the "new" feature transfers the
+	    ownership to the result object.
+	    
+	    The feature/solution could also be used in other languages
+	    that use gc and implement the inplace operators, or other
+	    operators, in a similar way.
+
 04/07/2004: cheetah (William Fulton)
             [C#] C++ enums are no longer wrapped by integers, they are now wrapped by 
             C# enums. For Example, given C++: