Re: address of virtual member function passed as template argument

From:
pascal.zschumme@gmail.com
Newsgroups:
microsoft.public.vc.language
Date:
19 Mar 2007 07:43:13 -0700
Message-ID:
<1174315393.835475.49540@n59g2000hsh.googlegroups.com>
On 19 Mrz., 00:10, "Alex Blekhman" <x...@oohay.moc> wrote:

<pascal.zschu...@gmail.com> wrote:

[...]
I want to use Boost.Property and therefor it need to pass
those
addresses to boost::property::object_property<...>

consider the following example:
<code>
class foo
{
private:
int value;

public:
int getValue() const { return value; }
void setValue(const int& v) { value = v; }

boost::scalar_property< boost::object_property
<
char, foo,
&foo::getValue,
&foo::setValue

Value;

};
</code>

If you make getValue() oder setValue() virtual, it
crashes.
Well, i could pass pointers to getValue and setValue to
the property
using it's custuctor at RunTime.
But i had to write my own property-lib for that and (more
importantly)
it wouldn't fit into my OOP-system that well. (would be
better if
every devired class _had_ to use getValue and setValue for
their
properties)


I'm not sure whether following code will fit into your
OOP-system or not, but here's the possible solution using
VC++ specific extension:

<code>

class foo
{
private:
 int value;

public:
 virtual int getValue() const { return value; }
 virtual void setValue(const int& v) { value = v; }

    __declspec(property(
        get = getValue, put = setValue)) int Value;

};

...

foo f;
f.Value = 42; // foo::setValue is called

</code>

Alex


Hi Alex

Nice Hint, thank you.
It's a pitty that there are no std c++ properties.

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