in both cases, it is eventually assigned to $item.

No, nothing is being assigned to $item. Rather, in the error case, $item becomes an alias, i.e. an alternate way to access the same instance of the constant string "abcdef".

In reply to Re^2: Still don't undersand "Modification of a read-only value attempted" error by Eliya
in thread Still don't undersand "Modification of a read-only value attempted" error by Anonymous Monk

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