projects / rustc.git / blame
| Commit | Line | Data |
|---|---|---|
| 8bb4bdeb XL |
1 | This crate provides a safe interface `libc`'s `memchr` and `memrchr`. |
| 2 | This crate also provides fallback implementations when either function is | |
| 3 | unavailable. | |
| 4 | ||
| 5 | [](https://travis-ci.org/BurntSushi/rust-memchr) | |
| 6 | [](https://ci.appveyor.com/project/BurntSushi/rust-memchr/branch/master) | |
| 7 | [](https://crates.io/crates/memchr) | |
| 8 | ||
| 9 | Dual-licensed under MIT or the [UNLICENSE](http://unlicense.org). | |
| 10 | ||
| 11 | ||
| 12 | ### Documentation | |
| 13 | ||
| 14 | [https://docs.rs/memchr](https://docs.rs/memchr) | |
| 15 | ||
| 16 | ### no_std | |
| 17 | ||
| 18 | memchr links to the standard library by default, but you can disable the | |
| 19 | `use_std` feature if you want to use it in a `#![no_std]` crate: | |
| 20 | ||
| 21 | ```toml | |
| 22 | [dependencies] | |
| 23 | memchr = { version = "1.0", default-features = false } | |
| 24 | ``` | |
| 25 | ||
| 26 | ### Performance | |
| 27 | ||
| 28 | On my system (Linux/amd64), `memchr` is about an order of magnitude faster than | |
| 29 | the more idiomatic `haystack.iter().position(|&b| b == needle)`: | |
| 30 | ||
| 31 | ``` | |
| 32 | test iterator ... bench: 5,280 ns/iter (+/- 13) = 1893 MB/s | |
| 33 | test iterator_reversed ... bench: 5,271 ns/iter (+/- 7) = 1897 MB/s | |
| 34 | test libc_memchr ... bench: 202 ns/iter (+/- 0) = 49504 MB/s | |
| 35 | test libc_memrchr ... bench: 197 ns/iter (+/- 1) = 50761 MB/s | |
| 36 | ``` |