Re: Providing pure virtual functions with a body

From:

Alberto Ganesh Barbati <AlbertoBarbati@libero.it>

Newsgroups:

comp.lang.c++.moderated

Date:

17 Oct 2006 14:33:43 -0400

Message-ID:

<np7Zg.7028$Fk1.13716@twister2.libero.it>

CellDivider ha scritto:

class A {

virtual void f() = 0;
};

A::f() { <.......> }

My question is, where in the standard can you read that this is
possible? The only reference I found is this

10.4 para 2:

.. . . [Note: a function declaration cannot provide both a
pure-specifier and a definition -end note]

Is that all or is it mentioned more explicit anywhere? Because that
would be a little bit reading-between-the-lines I think...

It's not explicitly impossible, so it's possible :-D

Anyway, the line you quote is not the only reference. In the very same
paragraph, just few lines above your quote, I read "A pure virtual
function need be defined only if explicitly called with the qualified-id
syntax (5.1)." So not only it hints to the possibility that an abstract
function can be defined, but also provide a necessity condition.

Ganesh

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