In do_something you replace the passed in hash reference you copied into $hash with a new hash so the original hash doesn't get altered.

In do_something_else you use the copied reference to access the original hash and update it.

In both cases $hash starts out with a reference to the original hash.

Premature optimization is the root of all job security

In reply to Re: hash question by GrandFather
in thread hash question by duyet

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