Re: [PATCH] contrib/diff-highlight: multibyte characters diff

From: Jeff King <peff@peff.net>
Date: Feb 13, 2014, 01:37 UTC
Message-ID: <20140213013751.GA11355@sigill.intra.peff.net>
In-Reply-To: <20140213011753.GD4582@vauxhall.crustytoothpaste.net>

On Thu, Feb 13, 2014 at 01:17:54AM +0000, brian m. carlson wrote:

Show 18 quoted lines

> On Wed, Feb 12, 2014 at 06:27:40PM -0500, Jeff King wrote:
> > On Wed, Feb 12, 2014 at 11:10:49PM +0000, Thomas Adam wrote:
> > 
> > > On 12 February 2014 20:59, Jeff King <peff@peff.net> wrote:
> > > > +sub decode {
> > > > +       my $orig = shift;
> > > > +       my $decoded = eval { decode_utf8($orig, Encode::FB_CROAK) };
> > > > +       return defined $decoded ?
> > > 
> > > I'd still advocate checking $@ here, rather than the defined $decoded check.
> > 
> > I don't mind changing it, but for my edification, what is the advantage?
> 
> The documentation for decode_utf8 isn't clear, but I don't know if it
> can ever return undef.  What, for example, does it return if $orig is
> not defined?  That's the benefit: it's immediately clear to the user
> that you're interested in whether it threw an exception, rather than
> whether it produced a given value.

I'd argue that I am more interested in whether it returned a value. Let us imagine for a moment that decode_utf8 could return undef without throwing an exception. What should the function return in such a case?

I think the only sensible thing is the original (and to indicate that the result was not converted).

-Peff