Algori...M97_001(3pm)

🎀 Algori...M97_001(3pm) 🎀

okay bestie, this is a page from the User Contributed Perl Documentation manual, and it's about CheckDigits::M97_001 — the module that does check digits for Belgian VAT Registration Numbers (BE). yes that's a lot of acronyms, no we're not scared of them 💅

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✨ NAME ✨

CheckDigits::M97_001 — compute check digits for VAT Registration Number (BE) 💖

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🦋 SYNOPSIS 🦋

here's the whole vibe, copy-paste ready:

use Algorithm::CheckDigits;

$ustid = CheckDigits('ustid_be');

if ($ustid->is_valid('136695962')) {
      # do something
}

$cn = $ustid->complete('1366959');
# $cn = '136695962'

$cd = $ustid->checkdigit('136695962');
# $cd = '62'

$bn = $ustid->basenumber('136695962');
# $bn = '1366959'

slay. it's giving "four methods, four little errands, zero drama" 🌸

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🔥 DESCRIPTION 🔥

⭐ ALGORITHM ⭐

the whole tea, in two steps, no skips:

1. take the whole number (without the checksum) and do it modulo 97.
2. the checksum is the difference of the remainder from step 1 to 97.

that's it. that's the algorithm. lowkey elegant fr fr.

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💅 METHODS 💅

is_valid($number)

returns true if $number is made up of nothing but numbers, and the last digit is a valid check digit per the algorithm up above 👑

a leading 'BE' before the numbers gets ignored, bestie — it's just vibes, not data.

returns false otherwise.

complete($number)

the check digit for $number gets computed and then concatenated onto the end of $number.

returns the complete number with the check digit, or '' if $number doesn't consist solely of digits and spaces 😭

and a leading 'BE' before the digits? ignored for the computation, but retained for the result. main character energy, it stays. ✨

basenumber($number)

returns the basenumber of $number, but only if $number has a valid check digit.

a leading 'BE' before the digits gets ignored and is not returned with the result — ghosted, honestly 🫶

returns '' otherwise.

checkdigit($number)

returns the checkdigits of $number, but only if $number has a valid check digit.

returns '' otherwise.

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🌈 EXPORT 🌈

none by default. as it should be, honestly. nothing jumping out at you unprompted 💜

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👑 AUTHOR 👑

Mathias Weidner, "<mamawe@cpan.org>" 🎀

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🌸 SEE ALSO 🌸

• perl
• CheckDigits
• <http://www.pruefziffernberechnung.de>
• <https://en.wikipedia.org/wiki/VAT_identification_number>

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and that's the whole page bb 💖 this was perl v5.36.0, dated 2022-10-13, filed under Algori...M97_001(3pm) — go forth and validate those Belgian VAT numbers, icon. periodt. 🌈💅🦋