I'm confused on just what you're trying to do. I'm not sure you aren't as well.

# How to create a hash with keys only?

That's nonsensical. Keys are a way to find a value. You can create a hash of keys whose value is undef or 0 or an empty string or any temporary placeholder you want, but you can't have a "hash with keys only". 

@insert = \%hash;

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This creates a 1-array whose first element is a reference to an empty hash. I don't think that's what you want to do.

The rest of the code is at least superficially reasonable (if you put %ages before the lines where you try and reference it), but what's the purpose of %hash? What are you wanting to end up with?

In reply to Re: array/hash - reference and dereference by fullermd
in thread array/hash - reference and dereference by Anonymous Monk

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