You are adding memory addresses.

If you change what $b points to, the add it to $a, the $sum will change.

You state : I make a change to hashref $b

Did you change the internal content of the hashref, or did you assign a new hashref to $b ? (Thereby changing the memory address)

        ...it is unhealthy to remain near things that are in the process of blowing up.     man page for WARP, by Larry Wall

In reply to Re: Addition of hashes by NetWallah
in thread Addition of hashes by the_dark_lord

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