See Juerd's original thread: Non-destructive array processing for some explanation/discussion.

How it works, as I understand, and anyone knows better, please correct me.

When you pass an array to a sub, each of the elements of @_ is alias to the elements of the original array. As the destructive manipulations are applied to @_ rather than the original array, the original array and it's contents remain untouched by the process.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^5: Unobvious Pathological Code Snippets by BrowserUk
in thread Unobvious Pathological Code Snippets by QM

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