why, using the -> notation, keys do not go in quotes?

They do -- the quotes are just optional. You might need the quotes if the key name collides with a built-in function such as 'shift'

In the following, what is the type of mykey? $myhash_ref->{mykey};

That would be equal to the string 'mykey'

In reply to Re^2: Array of Hashes by Anonymous Monk
in thread Array of Hashes by tobeythorn

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