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Date: Thu, 10 Dec 2009 20:04:56 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] Re: [FOR 0.12 PATCH 2/4] pci: don't hw_error()
	when no slot is available.
Message-ID: <20091210180455.GA20205@redhat.com>
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To: Gleb Natapov <gleb@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>, qemu-devel@nongnu.org

On Thu, Dec 10, 2009 at 03:22:52PM +0200, Gleb Natapov wrote:
> On Thu, Dec 10, 2009 at 02:23:05PM +0200, Michael S. Tsirkin wrote:
> > On Thu, Dec 10, 2009 at 01:19:10PM +0100, Gerd Hoffmann wrote:
> > >   Hi,
> > >
> > >>> +    if (pci_dev == NULL) {
> > >>> +        hw_error("PCI: can't register device\n");
> > >>> +    }
> > >>
> > >> Can you please use !pci_dev for these checks?
> > >
> > > Why?  IMHO the code is more readable that way.  It is easy to miss a  
> > > single '!' character when reading the code, so I tend to write such  
> > > tests in a more verbose fashion.
> > >
> > > cheers,
> > >   Gerd
> > 
> > Reader has limited short term memory. Don't fill it up with
> > irrelevant detail. In places where it might be confusing,
> > a comment might be appropriate, this is not one of them.
> > 
> > C is a terse language. !x is a standard idiom. Let's use it.
> > 
> ! is for boolean.

In which language? Not in C.

> pci_dev is not boolean.
> --
> 			Gleb.