Got a problem with peeking hash elements without breaking iterator. According to perldocs, using keys or values on %hash variable resets the internal hash iterator, used by keys/values/each. But seems not only. Simple copying of hash via %other_hash = %hash resets iterator for %hash too.

For example:

my %hash = ('Hello' => 'World');
while ( my ( $key, $value ) = each %hash ) {
    my %otherhash = %hash;
    print "\n$key=$value";
}

[download]

So question: how can I peek hash keys and values without breaking it?

In case of "why, oh why do you need this?", here is the case: my debugger for IntelliJ IDEA sends current lexical variables to the IDE on each step in/over/etc. And in case of hashes, sends number of elements and elements (by request). But when I'm trying to do so - iterator resets and loop becames infinite. Haven't tried Storable yet, but it seems too expensive anyway.

In reply to Peek a hash without breaking iterator by hurricup

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