From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Wong <normalperson@yhbt.net>
Subject: Re: [PATCH] git-svn: Destroy the cache when we fail to read it
Date: Tue, 23 Aug 2011 12:58:37 -0700
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Cc: Jason Gross <jgross@MIT.EDU>, git@vger.kernel.org,
	Jonathan Nieder <jrnieder@gmail.com>
To: Junio C Hamano <gitster@pobox.com>
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Junio C Hamano <gitster@pobox.com> wrote:
> Eric Wong <normalperson@yhbt.net> writes:
> > Jason Gross <jgross@MIT.EDU> wrote:
> >>  		my $cache_path = "$ENV{GIT_DIR}/svn/.caches/";
> >
> > Can we make the caches sharable by encoding variables like
> > $Config{use64bitint} and $Storable::VERSION into $cache_path?
> >
> > Something like this (untested):
> >
> > 	use Config;
> >
> > 	my $cache_path = "$ENV{GIT_DIR}/svn/.caches/";
> > 	$cache_path .= "$Config{use64bitint}.$Storable::VERSION/";
> >
> > We'll blow everybody's cache away once during the git-svn upgrade, but
> > in the future people will be able to share the same working tree between
> > different versions of perl/Storable/whatnot without needing extra code
> > to detect croaks, different build options, and nuking each other's
> > caches.
> 
> Meaning multiple directories and people share with those with systems with
> similar characteristics?

Yes.

> It certainly is better than silently getting confused or barfing when
> reading 32LE data on 64BE box, and presumably it would be easy to
> implement, but is that the best we can do with memoize?
> 
> I am wondering if memoize can be told to use a platform independent
> serializer backend that is reasonably efficient.

Storable nstore only guarantees endian-neutrality.  JSON/YAML/XML are
all platform-neutral options but (AFAIK) none are standard parts of all
Perl versions we support.  There's Data::Dumper + eval which should
work, but a Memoize::* interface needs to be implemented/imported.

-- 
Eric Wong