Re: Returning Nulls in Templates

From:

Ruben Safir <ruben@mrbrklyn.com>

Newsgroups:

comp.lang.c++

Date:

Mon, 21 Mar 2011 17:01:16 +0000 (UTC)

Message-ID:

<im808s$4v8$11@reader1.panix.com>

On Sun, 20 Mar 2011 13:53:17 +0000, Leigh Johnston wrote:

On 20/03/2011 09:17, Alf P. Steinbach /Usenet wrote:

* Ruben Safir, on 20.03.2011 06:37:

inline unk value();

It's not necessary to designate the method as 'inline', since it's in a
template.

On the other hand you should have a 'const' at the end there.

inline unk& value_ref();
inline void value(unk);

When you have exposed a member in all ways possible, and that's roughly
what you have done here, what's the point of having that member
non-'private'?

In this case, nothing.

Remove the accessor and modifier stuff. Just make that value 'public'.

I disagree; instead I would do:

const unk& value() const;
unk& value();
void set_value(const unk&);

/Leigh

If I define value() as a const returning a const reference, then I can't
change the value when using the operator[] and I'd think defeats the
purpose of making it a reference in the first place ..

mylist[2] = mylust[3];

I broke value() into two different methods, one returning the reference

unk Node::value() const{
return value_;
}

unk& Node::value_ref(){
return value_;
}

The second one allows the referenced value to be swapped with the operator
[], the first copies the value into the next scope level without it being
able to affect the object value.

It is only for the specifics of operator[] that I can see any need to
change val_ref() and perhaps I should make that private method.

Ruben