Let's say you have an array of hashes. Well, that's really an array of hash references. If you do foreach my $x (my @b = @a), what you're doing is making a copy of the hash references. So, $x = 3; won't affect @a, but $x->{foo} = 3; will affect $a[2]{foo}, if $x was aliased to the third element in @a, for instance.

A deep copy will make a copy of both @a and everything that each element in @a might have, should they be references themselves to stuff, and if that stuff is a reference, etc.

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We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

In reply to Re^3: Preserve array contents in for() loop by dragonchild
in thread Preserve array contents in for() loop by dda

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