icu_locid/extensions/transform/
key.rs

1// This file is part of ICU4X. For terms of use, please see the file
2// called LICENSE at the top level of the ICU4X source tree
3// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
4
5impl_tinystr_subtag!(
6    /// A key used in a list of [`Fields`](super::Fields).
7    ///
8    /// The key has to be a two ASCII characters long, with the first
9    /// character being alphabetic, and the second being a number.
10    ///
11    /// # Examples
12    ///
13    /// ```
14    /// use icu::locid::extensions::transform::Key;
15    ///
16    /// let key1: Key = "k0".parse().expect("Failed to parse a Key.");
17    ///
18    /// assert_eq!(key1.as_str(), "k0");
19    /// ```
20    Key,
21    extensions::transform,
22    key,
23    extensions_transform_key,
24    2..=2,
25    s,
26    s.all_bytes()[0].is_ascii_alphabetic() && s.all_bytes()[1].is_ascii_digit(),
27    s.to_ascii_lowercase(),
28    s.all_bytes()[0].is_ascii_lowercase() && s.all_bytes()[1].is_ascii_digit(),
29    InvalidExtension,
30    ["k0"],
31    ["", "k", "0k", "k12"],
32);