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37 строки
1.3 KiB
Markdown
37 строки
1.3 KiB
Markdown
This crate provides a safe interface `libc`'s `memchr` and `memrchr`.
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This crate also provides fallback implementations when either function is
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unavailable.
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[](https://travis-ci.org/BurntSushi/rust-memchr)
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[](https://ci.appveyor.com/project/BurntSushi/rust-memchr/branch/master)
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[](https://crates.io/crates/memchr)
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Dual-licensed under MIT or the [UNLICENSE](http://unlicense.org).
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### Documentation
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[https://docs.rs/memchr](https://docs.rs/memchr)
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### no_std
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memchr links to the standard library by default, but you can disable the
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`use_std` feature if you want to use it in a `#![no_std]` crate:
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```toml
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[dependencies]
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memchr = { version = "1.0", default-features = false }
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```
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### Performance
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On my system (Linux/amd64), `memchr` is about an order of magnitude faster than
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the more idiomatic `haystack.iter().position(|&b| b == needle)`:
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```
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test iterator ... bench: 5,280 ns/iter (+/- 13) = 1893 MB/s
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test iterator_reversed ... bench: 5,271 ns/iter (+/- 7) = 1897 MB/s
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test libc_memchr ... bench: 202 ns/iter (+/- 0) = 49504 MB/s
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test libc_memrchr ... bench: 197 ns/iter (+/- 1) = 50761 MB/s
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```
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