are there cases where $v could get overwritten

The regex match operator (=~) never modifies its left operand, so no.

if by chance the string comparison doesn't have my expected timestamp on the end

Is that really a possibility?

Computers don't generally do things "by chance". Especially in what by their very nature, have to be very controlled environments like Amazon's EC2.

So, unless you have actual experience, or documentation to suggest that it is a possibility, you are being over-defensive to the point of paranoia.

As for speeding up the hash building process, based on the information supplied, probably all you need is:

my %snapshot_roster = map {
    m[(snap-\S+).+-(\d+)$]
} @snapshot_listing;

[download]

Which should be measurably quicker.

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.

In reply to Re: HoA create from array using map, more efficient? by BrowserUk
in thread HoA create from array using map, more efficient? by hsinclai

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