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
70 mod macros;
71
72 mod ascii;
73 mod asciibyte;
74 mod error;
75 mod int_ops;
76 mod unvalidated;
77
78 #[cfg(feature = "serde")]
79 mod serde;
80
81 #[cfg(feature = "databake")]
82 mod databake;
83
84 #[cfg(feature = "zerovec")]
85 mod ule;
86
87 #[cfg(any(feature = "serde", feature = "alloc"))]
88 extern crate alloc;
89
90 pub use ascii::TinyAsciiStr;
91 pub use error::ParseError;
92 pub use unvalidated::UnvalidatedTinyAsciiStr;
93
94 /// These are temporary compatability reexports that will be removed
95 /// in a future version.
96 pub type TinyStr4 = TinyAsciiStr<4>;
97 /// These are temporary compatability reexports that will be removed
98 /// in a future version.
99 pub type TinyStr8 = TinyAsciiStr<8>;
100 /// These are temporary compatability reexports that will be removed
101 /// in a future version.
102 pub type TinyStr16 = TinyAsciiStr<16>;
103
104 #[test]
test_size()105 fn 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 }
115