Re^2: Can I serialize an object and have it remember it's type?

in reply to Re: Can I serialize an object and have it remember it's type?
in thread Can I serialize an object and have it remember it's type?

Evaling didn't work in this case, but thanks for your comment. I didn't realize that was how serialization was supposed to work, but now this all makes more sense. I'm going to try serializing and evaling with Storable now.
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Update, yep, this works.

use strict;
use warnings;
use Storable qw(store retrieve freeze thaw dclone);
use LWP::UserAgent;
use Test::More qw(no_plan);

my $user_agent = LWP::UserAgent->new;
isa_ok($user_agent, 'LWP::UserAgent');
store($user_agent, 'myuseragent') or die "Can't store useragent!\n";
my $user_agent2 = retrieve('myuseragent');
isa_ok($user_agent2, 'LWP::UserAgent');
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Comment on Re^2: Can I serialize an object and have it remember it's type? Download Code

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Re^3: Can I serialize an object and have it remember it's type? by Tanktalus (Canon) on Jul 21, 2005 at 14:14 UTC
Be forewarned - Storable does not provide forward/backward compatability. That is, if you upgrade your perl, there is a significant chance that all your stored objects will be unretrievable. If you switch platforms, it's almost guaranteed (use nstore - that may help). At least, that was my experience with Storable, oh so many years ago. I'd be happy to hear that has changed.	[reply]
Re^4: Can I serialize an object and have it remember it's type? by cowboy (Friar) on Jul 21, 2005 at 17:28 UTC
We use storable extensively on many different systems with very little trouble. Version problems are potentially still there, but only if a newer version stores a data type that an older version cannot handle. (it now will try to handle the data from the newer storable instead of just croaking) I second your comment about nstore though. I'd highly recommend using nstore by default. Having to convert a couple million stored objects because you add a 64bit machine to your farm of 32bit machines sucks.	[reply]
Re^3: Can I serialize an object and have it remember it's type? by tlm (Prior) on Jul 21, 2005 at 13:39 UTC
Evaling didn't work in this case... How exactly did it fail? ~~Does the error go away if you precede the `eval`'ing with `my $VAR1;`?~~ I'm going to try serializing and evaling with Storable now. With Storable explicit `eval`'ing is not required; just use its `store` and `retrieve` functions. Update: Gah! I entirely missed that in the serialization string the blessing had the wrong class. As tphyahoo kindly points out, no amount of `eval`-ing will fix this. the lowliest monk	[reply]
Re^4: Can I serialize an object and have it remember it's type? by tphyahoo (Vicar) on Jul 21, 2005 at 13:52 UTC
Thanks again tlm. As you can see above, I got the thing working with storable. As to the failure with DBM::Deep, I don't think evaling will help here because, if you look at the Dumper output, it's clear that this is getting blessed into a DBM::Deep object, and LWP::UserAgent is never mentioned.	[reply]

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