I'm writing a script that occasioanlly needs to save its state, make a guess and see if that guess leads to a logical end result. If the guess is bad, we need to backtrack and restore state. The main information is stored in a hash whose values are AoAs. e.g.:
$hash{$a}->[$b]->[$c] = $d;

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When I need to save state, I do something like this:
sub save_state
{
 my %save_hash = %main_hash;
 my @save_info;
 
 push(@save_info,\%save_hash);
 push(@save_info,\$aVar);
 # etc. for all vars to save
 
 push(@save_stack,\@save_info);
}

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That part works fine. The problems show up when I try to restore from the stack. It seems that any values I change in %main_hash are now in the %save_hash! Am I right to assume that this is somehow related to the fact that the values of the hash are array refs? Should I explicitly copy all of the info in the hash out before I save it?

Guildenstern
Negaterd character class uber alles!

In reply to References and state-saving by Guildenstern

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