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digitalmars.D.bugs - [Issue 10912] New: property overridding requires both accessors to be overridden

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=10912

           Summary: property overridding requires both accessors to be
                    overridden
           Product: D
           Version: D2
          Platform: All
               URL: http://dpaste.dzfl.pl/7bd529ae
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: burg.basile yahoo.com


--- Comment #0 from burg.basile yahoo.com 2013-08-27 11:37:05 PDT ---
When overriding a property setter in a descendant class, the getter must also
be overridden (or explicitly called with super), otherwise the compiler doesnt
understand we want to call the getter.

example:
---

import std.stdio;

class foo
{
    private int fMyField;
    public:
     property
    {
        void MyField(int aValue){fMyField = aValue;}
        int MyField(){return fMyField;}
    }
}

class bar: foo
{
    public:
     property
    {
        override void MyField(int aValue){fMyField = 0;}
    }    
    this()
    {
        writeln(MyField());// dmd should detect that the getter exists in foo.
        writeln(super.MyField());//super. would be superfluous
    }
}

void main(string[] args)
{
    auto Bar = new bar;
}
---

result: compile-time error, 
"Error: function f337.bar.MyField (int aValue) is not callable using argument
types ()"

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parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=10912


Andrej Mitrovic <andrej.mitrovich gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |andrej.mitrovich gmail.com
         Resolution|                            |INVALID


--- Comment #1 from Andrej Mitrovic <andrej.mitrovich gmail.com> 2013-08-27
19:42:59 PDT ---
Use:

alias super.MyField MyField;

in the 'bar' class. 

When you override only one overload of a function, the other functions are
hidden, unless you re-introduce the overloadset to the subclass. 

This is related to function hijacking, which you can read about here:
http://dlang.org/hijack.html

Although that page seems to miss the information about using 'alias super.name
name' for subclasses, it should probably be filed as a website bug.

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