tinystr/
lib.rs

Help
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
5//! `tinystr` is a utility crate of the [`ICU4X`] project.
6//!
7//! It includes [`TinyAsciiStr`], a core API for representing small ASCII-only bounded length strings.
8//!
9//! It is optimized for operations on strings of size 8 or smaller. When use cases involve comparison
10//! and conversion of strings for lowercase/uppercase/titlecase, or checking
11//! numeric/alphabetic/alphanumeric, `TinyAsciiStr` is the edge performance library.
12//!
13//! # Examples
14//!
15//! ```rust
16//! use tinystr::TinyAsciiStr;
17//!
18//! let s1: TinyAsciiStr<4> = "tEsT".parse().expect("Failed to parse.");
19//!
20//! assert_eq!(s1, "tEsT");
21//! assert_eq!(s1.to_ascii_uppercase(), "TEST");
22//! assert_eq!(s1.to_ascii_lowercase(), "test");
23//! assert_eq!(s1.to_ascii_titlecase(), "Test");
24//! assert!(s1.is_ascii_alphanumeric());
25//! assert!(!s1.is_ascii_numeric());
26//!
27//! let s2 = TinyAsciiStr::<8>::try_from_raw(*b"New York")
28//!     .expect("Failed to parse.");
29//!
30//! assert_eq!(s2, "New York");
31//! assert_eq!(s2.to_ascii_uppercase(), "NEW YORK");
32//! assert_eq!(s2.to_ascii_lowercase(), "new york");
33//! assert_eq!(s2.to_ascii_titlecase(), "New york");
34//! assert!(!s2.is_ascii_alphanumeric());
35//! ```
36//!
37//! # Details
38//!
39//! When strings are of size 8 or smaller, the struct transforms the strings as `u32`/`u64` and uses
40//! bitmasking to provide basic string manipulation operations:
41//! * `is_ascii_numeric`
42//! * `is_ascii_alphabetic`
43//! * `is_ascii_alphanumeric`
44//! * `to_ascii_lowercase`
45//! * `to_ascii_uppercase`
46//! * `to_ascii_titlecase`
47//! * `PartialEq`
48//!
49//! `TinyAsciiStr` will fall back to `u8` character manipulation for strings of length greater than 8.
50
51//!
52//! [`ICU4X`]: ../icu/index.html
53
54// https://github.com/unicode-org/icu4x/blob/main/documents/process/boilerplate.md#library-annotations
55#![cfg_attr(not(any(test, doc)), no_std)]
56#![cfg_attr(
57    not(test),
58    deny(
59        clippy::indexing_slicing,
60        clippy::unwrap_used,
61        clippy::expect_used,
62        clippy::panic,
63        clippy::exhaustive_structs,
64        clippy::exhaustive_enums,
65        clippy::trivially_copy_pass_by_ref,
66        missing_debug_implementations,
67    )
68)]
69
70mod macros;
71
72mod ascii;
73mod asciibyte;
74mod error;
75mod int_ops;
76mod unvalidated;
77
78#[cfg(feature = "serde")]
79mod serde;
80
81#[cfg(feature = "databake")]
82mod databake;
83
84#[cfg(feature = "zerovec")]
85mod ule;
86
87#[cfg(any(feature = "serde", feature = "alloc"))]
88extern crate alloc;
89
90pub use ascii::TinyAsciiStr;
91pub use error::ParseError;
92pub use unvalidated::UnvalidatedTinyAsciiStr;
93
94/// These are temporary compatability reexports that will be removed
95/// in a future version.
96pub type TinyStr4 = TinyAsciiStr<4>;
97/// These are temporary compatability reexports that will be removed
98/// in a future version.
99pub type TinyStr8 = TinyAsciiStr<8>;
100/// These are temporary compatability reexports that will be removed
101/// in a future version.
102pub type TinyStr16 = TinyAsciiStr<16>;
103
104#[test]
105fn test_size() {
106    assert_eq!(
107        core::mem::size_of::<TinyStr4>(),
108        core::mem::size_of::<Option<TinyStr4>>()
109    );
110    assert_eq!(
111        core::mem::size_of::<TinyStr8>(),
112        core::mem::size_of::<Option<TinyStr8>>()
113    );
114}
tinystr/lib.rs

tinystr/
lib.rs
