Crate just_a_tag

source ·
Expand description

Just a tag

This crate contains the Tag type, an RFC 1035 DNS label compatible string, with parsing FromStr and optional serde support.

Tag examples

assert_eq!(Tag::new("some-tag"), "some-tag");
assert_eq!(Tag::from_str("some-tag").unwrap(), "some-tag");
assert!(Tag::from_str("invalid-").is_err());

Unions of tags

A bit untrue to the crate’s name, it also provides the TagUnion type, which represents (unsurprisingly, this time) a union of tags.

use std::collections::HashSet;
use just_a_tag::{MatchesAnyTagUnion, Tag, TagUnion};

let union = TagUnion::from_str("foo").unwrap();
assert!(union.contains(&Tag::new("foo")));
assert_eq!(union.len(), 1);

let union = TagUnion::from_str("foo+bar").unwrap();
assert!(union.contains(&Tag::new("foo")));
assert!(union.contains(&Tag::new("bar")));
assert_eq!(union.len(), 2);

// TagUnions are particularly interesting when bundled up.
let unions = vec![
    TagUnion::from_str("bar+baz").unwrap(),
    TagUnion::from_str("foo").unwrap()
];

// foo matches
let set_1 = HashSet::from_iter([Tag::new("foo"), Tag::new("bar")]);
assert!(unions.matches_set(&set_1));

// bar+baz matches
let set_2 = HashSet::from_iter([Tag::new("fubar"), Tag::new("bar"), Tag::new("baz")]);
assert!(unions.matches_set(&set_2));

// none match
let set_3 = HashSet::from_iter([Tag::new("fubar"), Tag::new("bar")]);
assert!(!unions.matches_set(&set_3));

Structs

  • Tag
    A tag name.
  • TagUnion
    A tag union, e.g. foo or foo+bar+baz (i.e. foo and bar and baz).

Enums

Traits