cool! Thanks for sharing! (i mean, who doesn't like to read a good book!) Question: would it be worth considering internally having the digits be stored as half bytes for space usage? eg ISBN10 -> use ~ 5 bytes, and ISBN13 be ~ 7 bytes (this could be within a word64 as a tiny 8 slot array, OR or any sort of vector/array datatype)? (or instead of a decimal binary rep, pack it into a word64 as the number itself for either?) Granted this would complicate some of the internals engineering a teeny bit it looks like, in the current code, if there's no hyphens, it'll keep the input text value as the internal rep, *which can cause space leaks* if it's a slice of a much larger text input you otherwise do not intend to retain. When it generates its own text string, well... the text package uses utf16 (aka 2 bytes per character for valid ascii) as the internal rep, so the buffer representation will occupy 10 * 2 bytes or 13* 2bytes, so 20-26 bytes within the buffer, ignoring the extra word or two of indexing/offsets! point being ... it seems like could embed them (with a teeny bit of work) as follows data ISBN = IsIBSN10 ISBN10 | isISBN13 ISBN13 newtype ISBN10 = ISBN10 Word64 newtype ISBN13 = ISBN13 Word64 and then i'd probably be inclined to do use Data.Bits and do the "word 64 as a 16 slot array of word4's," which would also support the base 11 digit at the end encoding constraint, since word4 == base 16 :) then a teeny bit of work to do the right "right" ords and shows etc on this rep etc i hope the design i'm pointing out makes sense for you (and if i'm not being clear, please holler and i'll try to help) and again, thanks for sharing this! -Carter On Wed, Jul 29, 2020 at 1:39 PM Christian Charukiewicz via Haskell-Cafe < haskell-cafe@haskell.org> wrote:
Hello Haskell Cafe,
I wanted to share my first ever Haskell package: isbn
https://hackage.haskell.org/package/isbn
The package is motivated by my need to validate ISBNs (the unique identifier associated with every book published since 1970) in a Haskell application I am building. I published isbn as a back in May but yesterday I made some improvements the API and I think it is now ready to share as v1.1.0.0.
I have been using Haskell commercially for a few years, and have made several contributions to various packages, but as mentioned, this is my first time authoring and publishing a package. If anyone has any feedback, I would be happy to hear it.
Thank you,
Christian Charukiewicz _______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.