UUID

A simple UUID library and data type for Carp, conforming to RFC 4122 (and RFC 9562 for version 7), generatable in version 1, 4, and 7 for now.

Usage

You’ll be able to pull in the library using:

(load "git@github.com:carpentry-org/uuid@0.0.7")

You’ll then have access to the functions:

• UUID.str, which transforms it into a human-readable format, as defined in RFC 4122,
• UUID.valid?, which checks whether a string is a valid UUID,
• UUID.parse, which parses a string into a UUID data type (returning a Maybe),
• UUID.nil and UUID.max, the special all-zero Nil UUID and all-one Max UUID defined in RFC 9562 (§5.9 and §5.10), along with the UUID.nil? and UUID.max? predicates that test for them, and
• UUID4.generate, which generates a random UUID, conforming to UUID version 4.
• UUID1.generate, which generates a random UUID, conforming to UUID version 1. Currently the interface part of the UUID is always random (conforming to section 4.5 of the RFC).
• UUID7.generate, which generates a time-ordered UUID conforming to UUID version 7 (RFC 9562): a 48-bit Unix millisecond timestamp followed by a monotonic counter and random bits. Successive UUIDs sort in creation order under UUID.<, even when generated within the same millisecond, which makes them well suited as database keys.
• UUID7.timestamp, which extracts the millisecond timestamp back out of a version-7 UUID (as a Uint64).
• UUID.<, UUID.>, UUID.<=, and UUID.>=, which compare two UUIDs as unsigned big-endian 128-bit integers (byte by byte), ordering version-7 UUIDs chronologically.
• UUID.hash, which lets you use UUIDs as keys in a Map or Set.

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Have fun!