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7f45640401
This brings the code in line with my current style. It also inlines the dozen or so lines of code for FNV hashing instead of bringing in a micro-crate for it. Finally, it drops the dependency on regex in favor of using regex-syntax and regex-automata directly.
31 lines
765 B
Rust
31 lines
765 B
Rust
/// A convenience alias for creating a hash map with an FNV hasher.
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pub(crate) type HashMap<K, V> =
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std::collections::HashMap<K, V, std::hash::BuildHasherDefault<Hasher>>;
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/// A hasher that implements the Fowler–Noll–Vo (FNV) hash.
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pub(crate) struct Hasher(u64);
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impl Hasher {
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const OFFSET_BASIS: u64 = 0xcbf29ce484222325;
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const PRIME: u64 = 0x100000001b3;
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}
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impl Default for Hasher {
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fn default() -> Hasher {
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Hasher(Hasher::OFFSET_BASIS)
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}
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}
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impl std::hash::Hasher for Hasher {
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fn finish(&self) -> u64 {
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self.0
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}
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fn write(&mut self, bytes: &[u8]) {
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for &byte in bytes.iter() {
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self.0 = self.0 ^ u64::from(byte);
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self.0 = self.0.wrapping_mul(Hasher::PRIME);
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}
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}
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}
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