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digitalmars.D.bugs - [Issue 1645] New: can override base class' const method with non-const method

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1645

           Summary: can override base class' const method with non-const
                    method
           Product: D
           Version: 2.007
          Platform: All
        OS/Version: All
            Status: NEW
          Keywords: accepts-invalid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: schveiguy yahoo.com


This should not be allowed.  Otherwise, you can call a const method on a base
class and the derived class can change the object.

I believe the fix that should be implemented should follow the same rules as
today's override rules.  i.e., same function name/args, but derived method has
different const specicification results in a different signature, and therefore
a different overload.

Here is code that demonstrates the issue:

import std.stdio;

class A
{
  int x;
  const void f()
  {
    writefln("A");
  }
}

class B : A
{
  override void f()
  {
    x = 2;
    writefln("B");
  }
}

void main(){
  A y = new B;
  y.f;
}

[steves localhost svn]$ dmd testme.d
gcc testme.o -o 
testme -m32 -Xlinker -L/home/steves/dmd2/dmd/bin/../lib -lphobos2 -lpthread  
-lm
[steves localhost svn]$ ./testme
B
[steves localhost svn]$


--
Nov 07 2007
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1645


schveiguy yahoo.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical




------- Comment #1 from schveiguy yahoo.com  2008-10-21 10:57 -------
Bumping the severity up.  This really is a terrible bug, especially since we
are getting closer and closer to pure functions.  This bug has existed way too
long.


--
Oct 21 2008
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1645


bugzilla digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED




------- Comment #2 from bugzilla digitalmars.com  2009-04-01 13:51 -------
Fixed DMD 2.027


--
Apr 01 2009