hi, i have a hash like 
%hash=(
   a => 1
   b => 2
}

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How do I 'undef' a hash entry - not the value, but the key? if i write 
undef $hash{a}

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i get 
%hash=(
   a => undef
   b => 2
}

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What i want to get is 
%hash=(
   b => 2
}

[download]
I need this for %ENV modification (UX: unset equivalent).

In reply to 'undef'ing a hash element by Deda

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