.. _library_nanoid:

`nanoid`

This library generates random NanoID identifiers:

By default, identifiers are represented as atoms with 21 symbols and use the standard URL-safe alphabet:

_-0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ

Custom size, alphabet, and representation (atoms, lists of characters, or lists of character codes) are supported using a parametric object.

The generation of random identifiers uses the /dev/urandom random number generator when available. This includes macOS, Linux, \*BSD, and other POSIX operating systems. On Windows, a pseudo-random generator is used, randomized using the current wall time.

See also the ids, uuid, and ulid libraries.

API documentation

Open the `../../apis/library_index.html#nanoid <../../apis/library_index.html#nanoid>`__ link in a web browser.

Loading

To load all entities in this library, load the loader.lgt file:

| ?- logtalk_load(nanoid(loader)).

Testing

To test this library predicates, load the tester.lgt file:

| ?- logtalk_load(nanoid(tester)).

Usage

To generate an identifier using the default configuration:

| ?- nanoid::generate(NanoID). NanoID = 'V1StGXR8_Z5jdHi6B-myT' yes

To generate a 10-symbol identifier represented as a list of characters:

| ?- nanoid(chars, 10, 'abcdef012345')::generate(NanoID). NanoID = ['4','b','d','f','a','0','3','2','1','e'] yes

To generate a 32-symbol identifier represented as a list of character codes:

| ?- nanoid(codes, 32, [0'a,0'b,0'c,0'd,0'e,0'f,0'0,0'1,0'2,0'3])::generate(NanoID). NanoID = [49,97,99,100,48,102,98,101,50,51,48,101,99,102,49,50,98,100,49,97,48,51,101,98,100,99,49,102,48,97,50,100] yes