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Date: Fri, 20 Dec 2013 10:52:54 -0700
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Subject: Re: C++ overloaded virtual function
From: Alan Somers <asomers@freebsd.org>
To: Joe Nosay <superbisquit@gmail.com>
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On Fri, Dec 20, 2013 at 12:52 AM, Joe Nosay <superbisquit@gmail.com> wrote:
> /usr/home/raspycat/traverso/work/traverso-0.49.2/src/engine/Driver.h:49:14:
> note: hidden overloaded virtual function 'Driver::setup' declared
> here: different number of parameters (3 vs 4)
>         virtual int setup(bool capture=true, bool playback=true, const
> QString& cardDevice="none"
>
> Three = and one &, the last being the odd man out. Both spacing and
> removing the & still results in an error.
>
> Clang++ is expecting an absolute value such as the other three.
>
> How do I compensate for the & to have the same value type as =?

Your prototype calls the QString constructor within the prototype
itself.  I don't know if that's illegal, but it's certainly weird.  I
would try creating a global variable for "none", and reference that
object in the prototype, like this:

Driver.h:

QString NoneQString;
virtual int setup(bool capture=true, bool playback=true, const
QString& cardDevice=NoneQString);

Driver.cc
QString NoneQString("none");

-Alan

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