Generate ULIDs, TypeIDs and UPIDs

ulid() generates ULIDs: 48 bits of milliseconds and 80 random bits. Values from one session strictly increase, by the specification's rule: within a millisecond, the random component of the last value plus one. That overflows only after 2^80 values in one millisecond, which is a zuid_overflow_error.

Usage

ulid(n = 1, random = NULL, time = NULL)

typeid(n = 1, prefix, random = NULL, time = NULL)

upid(n = 1, prefix, random = NULL, time = NULL)

Arguments

n

The number of UUIDs.

random

NULL to draw from the operating system, or exactly the bytes needed: 10 per value for ULIDs and TypeIDs, 8 for UPIDs.

time

NULL for the current time, or a POSIXct (or a double of milliseconds since 1970) of length 1 or n.

prefix

For typeid(), the type: up to 63 lowercase letters and underscores, starting and ending with a letter, or "" for none. For upid(), one to four characters of 234567 and a to z, padded on the right with z as the reference pads it.

Value

A zuid vector of n values.

Details

typeid() generates TypeIDs: a version 7 UUID, as uuid() makes it, under prefix.

upid() generates UPIDs: 40 bits of time in 256 ms units, 64 random bits, the prefix and the current version, as the reference does. UPIDs are not monotonic within 256 ms.

Entropy comes from the operating system, never from R's random number generator, and the clock rollback rule of uuid() applies to ULIDs. As there, a call given both time and random is a pure function of its arguments.

Examples

ulid(2)
#> <zuid_ulid[2]>
#> [1] 01M6RCTH3B1CH6NNV3KAFR7CS0 01M6RCTH3B1CH6NNV3KAFR7CS1
typeid(2, "user")
#> <zuid_typeid[2]>
#> [1] user_01m6rcth3ceymtft2r0k7sv8yp user_01m6rcth3ceyn80b489hmpm7c8
upid(2, "user")
#> <zuid_upid[2]>
#> [1] user_2akv3ne6eccaywqqjpcdba user_2akv3ne6h5ytx437qedsda