Creating a hash value of a data structure

[Mark Fowler]

Shock horror Perl

Hi.  I want to create a hash value for a data structure, basically so that 
when I write the chart I'm creating with the routine to disk I can check 
if there's a recently created version already on disk before redoing the 
work.  Is there any accepted wisdom how to do this?

Ideas already considered:

 - Data dumper, then md5 it 
     won't work if the order of hash keys change (like it will when we 
     upgrade to 5.8.0 soonish

 - Storable, then md5 it
     Storable version changes write the data differently - hence bad
     keys for different versions.

This should be trivial.  Any ideas?

Later.

Mark.

-- 
s''  Mark Fowler                                     London.pm   Bath.pm
     http://www.twoshortplanks.com/              [EMAIL PROTECTED]
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){for(0..30){$|=print$t->Tgoto(cm,$_,$y)." $w";select$k,$k,$k,.03}$y+=2}