quidity suggests:
> %new_hash = map {defined($_) ? $_ : ''} %{$ref2};
In recent versions of Perl, you can also use a simpler version that modifies the hash in place: 
    map { $_ = '' unless defined } %$ref2;

[download]
This is comparable in simplicity to the original code that involved an array instead of a hash.

In reply to Re: setting values in anonymous hash by Dominus
in thread setting values in anonymous hash by agoth

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