> when changed, changes the keys ...

Well I think this is the easiest to answer, the basic mechanism is a hash-function mapping a key to an array-index for a lookup mechanism. °

And this means a stored key must be immutable , because that calculated array-index would change too.

Consequently there can't be a faster way than replacing the whole key-value pair with "delete OLD" + "store NEW".

All the other implementation details we discussed are about various other features and performance.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

°) That's why Perl's associative arrays are called "hashes" in the first place.

In reply to Re^4: can I change hash keys or values directly by LanX
in thread can I change hash keys or values directly by misterperl

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