A Rust library to generate and parse UUIDs.

Provides support for Universally Unique Identifiers (UUIDs). A UUID is a unique 128-bit number, stored as 16 octets. UUIDs are used to assign unique identifiers to entities without requiring a central allocating authority.

They are particularly useful in distributed systems, though can be used in disparate areas, such as databases and network protocols. Typically a UUID is displayed in a readable string form as a sequence of hexadecimal digits, separated into groups by hyphens.

The uniqueness property is not strictly guaranteed, however for all practical purposes, it can be assumed that an unintentional collision would be extremely unlikely.

Documentation

Add this to your Cargo.toml:

[dependencies]
uuid = "0.5"

and this to your crate root:

extern crate uuid;

To parse a simple UUID, then print the version and urn string format:

extern crate uuid;
use uuid::Uuid;

fn main() {
    let my_uuid = Uuid::parse_str("936DA01F9ABD4d9d80C702AF85C822A8").unwrap();
    println!("Parsed a version {} UUID.", my_uuid.get_version_num());
    println!("{}", my_uuid);
}

The library supports 5 versions of UUID:

To create a new random (V4) UUID and print it out in hexadecimal form, first you'll need to change how you depend on uuid:

[dependencies]
uuid = { version = "0.5", features = ["v4"] }

Next, you'll write:

extern crate uuid;
use uuid::Uuid;

fn main() {
    let my_uuid = Uuid::new_v4();
    println!("{}", my_uuid);
}

To create a new sha1-hash based (V5) UUID and print it out in hexadecimal form, you'll also need to change how you depend on uuid:

[dependencies]
uuid = { version = "0.5", features = ["v5"] }

Next, you'll write:

extern crate uuid;
use uuid::Uuid;

fn main() {
    let my_uuid = Uuid::new_v5(&uuid::NAMESPACE_DNS, "foo");
    println!("{}", my_uuid);
}

Wikipedia: Universally Unique Identifier