std: Stabilize custom hasher support in HashMap #31081
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r? @aturon cc @rust-lang/libs nominating for a beta-backport |
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Everything here seems reasonable and as was discussed. 👍 |
| pub fn with_hash_state(hash_state: S) -> HashMap<K, V, S> { | ||
| HashMap::with_hasher(hash_state) | ||
| } | ||
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| /// Creates an empty HashMap with space for at least `capacity` |
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Should we give the same warning about DoS here?
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Ooops, github just had it collapsed, nevermind.
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LGTM -- though I did leave one question about the actual API. I suspect I'm just failing to remember one of the design constraints here. |
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@aturon I've updated with removing the old and misleading |
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This looks good to go, right? |
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@alexcrichton corrected the wrong docs problem :) I still find the docs super misleading, but we can fix in post if you prefer. That's my only complaint. |
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I'm fine changing the docs, but I'm not really quite sure what to change them to? Do you have something in mind @aturon ? |
| @@ -190,6 +191,79 @@ pub trait Hasher { | |||
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| /// A trait representing an object which maintains state to create new instances | |||
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@alexcrichton Left some minimal suggestions. With that r=me. |
This commit implements the stabilization of the custom hasher support intended for 1.7 but left out due to some last-minute questions that needed some decisions. A summary of the actions done in this PR are: Stable * `std::hash::BuildHasher` * `BuildHasher::Hasher` * `BuildHasher::build_hasher` * `std::hash::BuildHasherDefault` * `HashMap::with_hasher` * `HashMap::with_capacity_and_hasher` * `HashSet::with_hasher` * `HashSet::with_capacity_and_hasher` * `std::collections::hash_map::RandomState` * `RandomState::new` Deprecated * `std::collections::hash_state` * `std::collections::hash_state::HashState` - this trait was also moved into `std::hash` with a reexport here to ensure that we can have a blanket impl to prevent immediate breakage on nightly. Note that this is unstable in both location. * `HashMap::with_hash_state` - renamed * `HashMap::with_capacity_and_hash_state` - renamed * `HashSet::with_hash_state` - renamed * `HashSet::with_capacity_and_hash_state` - renamed Closes rust-lang#27713
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This commit implements the stabilization of the custom hasher support intended for 1.7 but left out due to some last-minute questions that needed some decisions. A summary of the actions done in this PR are: Stable * `std::hash::BuildHasher` * `BuildHasher::Hasher` * `BuildHasher::build_hasher` * `std::hash::BuildHasherDefault` * `HashMap::with_hasher` * `HashMap::with_capacity_and_hasher` * `HashSet::with_hasher` * `HashSet::with_capacity_and_hasher` * `std::collections::hash_map::RandomState` * `RandomState::new` Deprecated * `std::collections::hash_state` * `std::collections::hash_state::HashState` - this trait was also moved into `std::hash` with a reexport here to ensure that we can have a blanket impl to prevent immediate breakage on nightly. Note that this is unstable in both location. * `HashMap::with_hash_state` - renamed * `HashMap::with_capacity_and_hash_state` - renamed * `HashSet::with_hash_state` - renamed * `HashSet::with_capacity_and_hash_state` - renamed Closes #27713
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Marking as accepted for beta as libs talked about this awhile ago |
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This commit implements the stabilization of the custom hasher support intended
for 1.7 but left out due to some last-minute questions that needed some
decisions. A summary of the actions done in this PR are:
Stable
std::hash::BuildHasherBuildHasher::HasherBuildHasher::build_hasherstd::hash::BuildHasherDefaultHashMap::with_hasherHashMap::with_capacity_and_hasherHashSet::with_hasherHashSet::with_capacity_and_hasherstd::collections::hash_map::RandomStateRandomState::newDeprecated
std::collections::hash_statestd::collections::hash_state::HashState- this trait was also moved intostd::hashwith a reexport here to ensure that we can have a blanket impl toprevent immediate breakage on nightly. Note that this is unstable in both
location.
HashMap::with_hash_state- renamedHashMap::with_capacity_and_hash_state- renamedHashSet::with_hash_state- renamedHashSet::with_capacity_and_hash_state- renamedCloses #27713