Try:

my( $bit1, $bit2 ) = unpack 'a4 a*', $uuid;

[download]

But, regarding your "more efficient than substr" remarks. For the sake of a single operation like this, you won't notice the difference; even if there actually is any.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re: How do unpack templates work by BrowserUk
in thread How do unpack templates work by unlinker

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