Crate tinystr

tinystr is a utility crate of the ICU4X project.

It includes TinyAsciiStr, a core API for representing small ASCII-only bounded length strings.

It is optimized for operations on strings of size 8 or smaller. When use cases involve comparison and conversion of strings for lowercase/uppercase/titlecase, or checking numeric/alphabetic/alphanumeric, TinyAsciiStr is the edge performance library.

Examples

use tinystr::TinyAsciiStr;

let s1: TinyAsciiStr<4> = "tEsT".parse().expect("Failed to parse.");

assert_eq!(s1, "tEsT");
assert_eq!(s1.to_ascii_uppercase(), "TEST");
assert_eq!(s1.to_ascii_lowercase(), "test");
assert_eq!(s1.to_ascii_titlecase(), "Test");
assert!(s1.is_ascii_alphanumeric());
assert!(!s1.is_ascii_numeric());

let s2 = TinyAsciiStr::<8>::try_from_raw(*b"New York")
    .expect("Failed to parse.");

assert_eq!(s2, "New York");
assert_eq!(s2.to_ascii_uppercase(), "NEW YORK");
assert_eq!(s2.to_ascii_lowercase(), "new york");
assert_eq!(s2.to_ascii_titlecase(), "New york");
assert!(!s2.is_ascii_alphanumeric());

Details

When strings are of size 8 or smaller, the struct transforms the strings as u32/u64 and uses bitmasking to provide basic string manipulation operations:

• is_ascii_numeric
• is_ascii_alphabetic
• is_ascii_alphanumeric
• to_ascii_lowercase
• to_ascii_uppercase
• to_ascii_titlecase
• PartialEq

TinyAsciiStr will fall back to u8 character manipulation for strings of length greater than 8.

Modules

ascii 🔒

asciibyte 🔒

error 🔒

int_ops 🔒

macros 🔒

ule 🔒

unvalidated 🔒

Macros

tinystr

Structs

TinyAsciiStr

UnvalidatedTinyAsciiStr

A fixed-length bytes array that is expected to be an ASCII string but does not enforce that invariant.

Enums

TinyStrError

Type Aliases

TinyStr4

These are temporary compatability reexports that will be removed in a future version.

TinyStr8

These are temporary compatability reexports that will be removed in a future version.

TinyStr16

These are temporary compatability reexports that will be removed in a future version.