Math::NoCarry(3pm)

✨ NAME ✨

Math::NoCarry — a Perl extension for no-carry arithmetic 💅 (it lives in the User Contributed Perl Documentation, section 3pm, iykyk)

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🎀 SYNOPSIS 🎀

use Math::NoCarry qw(:all);

my $sum        = add( 123, 456 );

my $difference = subtract( 123, 456 );

my $product    = multiply( 123, 456 );

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🦋 DESCRIPTION 🦋

okay bestie, listen. No-carry arithmetic is literally just... not letting yourself carry digits over to the next column. that's the whole vibe. 🫶

so like, normally when you add 8 and 4 you get 12, right? but that little 1 is a carry, and no-carry arithmetic said "not today." so the no-carry sum of 8 and 4 is just 2. periodt. in effect, it's addition modulo 10 in each column. here's the classic demo where I discard ALL the carry digits:

         1234
       + 5678
       ------
         6802

For multiplication, the result of pair-wise multiplication of digits is the modulo 10 value of their normal, everyday multiplication. slay.

         123
       x 456
       -----
           8   6 x 3
          2    6 x 2
         6     6 x 1

          5    5 x 3
         0     5 x 2
        5      5 x 1

         2     4 x 3
        8      4 x 2
     + 4       4 x 1
     -------
       43878

and since multiplication and subtraction are actually types of additions, you can multiply and subtract like this as well. no cap. 🔥

No carry arithmetic is both associative and commutative. it's giving mathematically well-behaved. 👑

🌸 Functions 🌸

As of version 1.11, all of these functions are exportable on demand, or with the tag ":all" to get them all at once. yes bestie, one tag, everything. 🎁

• multiply( A, B ) — Returns the no carry product of A and B.

Returns A if it is the only argument ( A x 1 );

• add( A, B ) — Returns the no carry sum of the positive numbers A and B.

Returns A if it is the only argument ( A + 0 )

Returns false if either number is negative. 🙈

• subtract( A, B ) — Returns the no carry difference of the positive numbers A and B.

Returns A if it is the only argument ( A - 0 )

Returns false if either number is negative. 🙈

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💀 BUGS 💀

• none reported yet :) 💖 (iconic, honestly. we love a clean bug tracker.)

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⭐ TO DO ⭐

• this could be a full object package with overloaded +, *, and - operators 👀
• it would be nice if I could give the functions more than two arguments.
• addition and subtraction don't do negative numbers. 💀

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🌈 SOURCE AVAILABILITY 🌈

This source is in GitHub:

https://github.com/briandfoy/math-nocarry

go star it bestie, it's free. ⭐

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👑 AUTHOR 👑

brian d foy, "<briandfoy@pobox.com>" 🫶

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🍓 COPYRIGHT AND LICENSE 🍓

Copyright © 2002-2025, brian d foy <briandfoy@pobox.com>. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the terms of the Artistic License 2.0. 💅

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and that's the whole page, bestie!! this lil number ships with perl v5.40.1 and the page itself is dated 2025-04-19 — Math::NoCarry(3pm), literally the moment. mwah. 💖✨🎀🦋