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Relax some Hash bounds on HashMap<K, V, S> and HashSet<T, S> #58370

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merged 1 commit into from
Feb 25, 2019

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nox
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@nox nox commented Feb 11, 2019

Notably, hash iterators don't require any trait bounds to be iterated.

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@rust-highfive rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Feb 11, 2019
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r? @Amanieu

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r? @alexcrichton

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Centril commented Feb 11, 2019

Could you give a full example of when this would be useful? In particular, to construct a HashMap you need to show that K: Eq + Hash, S: BuildHasher.

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The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.
travis_time:end:042adcf4:start=1549889491878821295,finish=1549889636913451617,duration=145034630322
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
[01:03:23] .................................................................................................... 2200/5380
[01:03:27] .................................................................................................... 2300/5380
[01:03:31] .................................................................................................... 2400/5380
[01:03:36] .................................................................................................... 2500/5380
[01:03:40] ..........................................F......................................................... 2600/5380
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[01:03:53] .................................................................................................... 2900/5380
[01:03:57] .................................................................................................... 3000/5380
[01:04:00] .................................................................................................... 3100/5380
---
[01:05:36] 
[01:05:36] ---- [ui] ui/issues/issue-35677.rs stdout ----
[01:05:36] diff of stderr:
[01:05:36] 
[01:05:36] - error[E0599]: no method named `drain` found for type `&mut std::collections::HashMap<K, V>` in the current scope
[01:05:36] -   --> $DIR/issue-35677.rs:3:10
[01:05:36] + error[E0599]: no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope
[01:05:36] 3    |
[01:05:36] 3    |
[01:05:36] - LL |     this.drain()
[01:05:36] -    |          ^^^^^
[01:05:36] + LL |     this.is_subset(other)
[01:05:36] 6    |
[01:05:36] 6    |
[01:05:36] -    = note: the method `drain` exists but the following trait bounds were not satisfied:
[01:05:36] -            `K : std::cmp::Eq`
[01:05:36] -            `K : std::hash::Hash`
[01:05:36] +    = note: the method `is_subset` exists but the following trait bounds were not satisfied:
[01:05:36] +            `T : std::cmp::Eq`
[01:05:36] +            `T : std::hash::Hash`
[01:05:36] 11 error: aborting due to previous error
[01:05:36] 12 
[01:05:36] 
[01:05:36] 
[01:05:36] 
[01:05:36] The actual stderr differed from the expected stderr.
[01:05:36] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/issue-35677.stderr
[01:05:36] To update references, rerun the tests and pass the `--bless` flag
[01:05:36] To only update this specific test, also pass `--test-args issues/issue-35677.rs`
[01:05:36] error: 1 errors occurred comparing output.
[01:05:36] status: exit code: 1
[01:05:36] status: exit code: 1
[01:05:36] command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/issues/issue-35677.rs" "-Zthreads=1" "--target=x86_64-unknown-linux-gnu" "--error-format" "json" "-Zui-testing" "-C" "prefer-dynamic" "-o" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/a" "-Crpath" "-O" "-Zunstable-options" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/auxiliary" "-A" "unused"
[01:05:36] ------------------------------------------
[01:05:36] 
[01:05:36] ------------------------------------------
[01:05:36] stderr:
[01:05:36] stderr:
[01:05:36] ------------------------------------------
[01:05:36] {"message":"no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope","code":{"code":"E0599","explanation":"\nThis error occurs when a method is used on a type which doesn't implement it:\n\nErroneous code example:\n\n```compile_fail,E0599\nstruct Mouth;\n\nlet x = Mouth;\nx.chocolate(); // error: no method named `chocolate` found for type `Mouth`\n               //        in the current scope\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/issues/issue-35677.rs","byte_start":106,"byte_end":115,"line_start":4,"line_end":4,"column_start":10,"column_end":19,"is_primary":true,"text":[{"text":"    this.is_subset(other)","highlight_start":10,"highlight_end":19}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the method `is_subset` exists but the following trait bounds were not satisfied:\n`T : std::cmp::Eq`\n`T : std::hash::Hash`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0599]: no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope\n  --> /checkout/src/test/ui/issues/issue-35677.rs:4:10\n   |\nLL |     this.is_subset(other)\n   |          ^^^^^^^^^\n   |\n   = note: the method `is_subset` exists but the following trait bounds were not satisfied:\n           `T : std::cmp::Eq`\n           `T : std::hash::Hash`\n\n"}
[01:05:36] {"message":"For more information about this error, try `rustc --explain E0599`.","code":null,"level":"","spans":[],"children":[],"rendered":"For more information about this error, try `rustc --explain E0599`.\n"}
[01:05:36] 
[01:05:36] ------------------------------------------
[01:05:36] 
---
[01:05:36] 
[01:05:36] thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:496:22
[01:05:36] 
[01:05:36] 
[01:05:36] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/compiletest" "--compile-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib" "--run-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib" "--rustc-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "--src-base" "/checkout/src/test/ui" "--build-base" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui" "--stage-id" "stage2-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-6.0/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "6.0.0\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"
[01:05:36] 
[01:05:36] 
[01:05:36] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test
[01:05:36] Build completed unsuccessfully in 0:04:38
[01:05:36] Build completed unsuccessfully in 0:04:38
[01:05:36] Makefile:48: recipe for target 'check' failed
[01:05:36] make: *** [check] Error 1
The command "stamp sh -x -c "$RUN_SCRIPT"" exited with 2.
travis_time:start:23a82bd0
$ date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)
Mon Feb 11 13:59:44 UTC 2019

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

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nox commented Feb 11, 2019

Could you give a full example of when this would be useful? In particular, to construct a HashMap you need to show that K: Eq + Hash, S: BuildHasher.

Short answer: I shouldn't have to add K: Eq + Hash, S: BuildHasher to a function that takes a hash map and just iterates it.

Long answer: I do fancy things in this project of mine, in which I pointer cast &HashMap<K, V, S> to &HashMap<Inert<K>, Inert<V>, Inert<S>> to provide a Sync way to access non-Sync values.

Also, all other collections (apart from BTreeMap<K, V> which I will handle in a separate PR) work this way, with an unbounded iter() implementation, and the Iterator implementations themselves of the various HashMap<K, V, S> iterators don't have those bounds.

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Centril commented Feb 11, 2019

Short answer: I shouldn't have to add K: Eq + Hash, S: BuildHasher to a function that takes a hash map and just iterates it.

That is dealt with by #44491.

Long answer: I do fancy things in this project of mine, in which I pointer cast &HashMap<K, V, S> to &HashMap<Inert<K>, Inert<V>, Inert<S>> to provide a Sync way to access non-Sync values.

Ah; thanks. Btw.. Inert should probably have #[repr(transparent)]?

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nox commented Feb 11, 2019

That is dealt with by #44491.

I don't think you can call that "dealt with", given that means adding bounds to that collection when, say, BTreeMap won't ever have any because that would be a breaking change.

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Centril commented Feb 11, 2019

That is dealt with by #44491.

I don't think you can call that "dealt with", given that means adding bounds to that collection when, say, BTreeMap won't ever have any because that would be a breaking change.

Yeah, that's fair.

/// let hasher: &RandomState = map.hasher();
/// ```
#[stable(feature = "hashmap_public_hasher", since = "1.9.0")]
pub fn hasher(&self) -> &S {
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I would prefer if this function kept the S: BuildHasher bound. I have some changes to hashbrown (which will soon replace the libstd hashmap) which may require this bound in the future.

Do you really need to call map.hasher() without a S: BuildHasher bound? If you really need it then I can try looking into a workaround, but it might get a bit ugly.

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Do you really need to call map.hasher() without a S: BuildHasher bound? If you really need it then I can try looking into a workaround, but it might get a bit ugly.

Nope, it was just one of the methods I saw that didn't need a bound, I can add it back.

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Please do.

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I moved it back where it was before with the same bounds.

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Amanieu commented Feb 11, 2019

Apart from my concern on hasher, I have no objection to the changes on iterators.

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The job x86_64-gnu-llvm-6.0 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.
travis_time:end:09a1dfec:start=1549902707222763773,finish=1549902805627259766,duration=98404495993
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout

Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
Setting environment variables from .travis.yml
$ export IMAGE=x86_64-gnu-llvm-6.0
---
[01:00:34] .................................................................................................... 2200/5380
[01:00:38] .................................................................................................... 2300/5380
[01:00:42] .................................................................................................... 2400/5380
[01:00:46] .................................................................................................... 2500/5380
[01:00:49] ...........................................F........................................................ 2600/5380
[01:00:57] .................................................................................................... 2800/5380
[01:01:01] .................................................................................................... 2900/5380
[01:01:05] .................................................................................................... 3000/5380
[01:01:08] .................................................................................................... 3100/5380
---
[01:02:31] 
[01:02:31] ---- [ui] ui/issues/issue-35677.rs stdout ----
[01:02:31] diff of stderr:
[01:02:31] 
[01:02:31] 1 error[E0599]: no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope
[01:02:31] +   --> $DIR/issue-35677.rs:4:10
[01:02:31] 3    |
[01:02:31] 3    |
[01:02:31] 4 LL |     this.is_subset(other)
[01:02:31] 
[01:02:31] 
[01:02:31] The actual stderr differed from the expected stderr.
[01:02:31] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/issue-35677.stderr
[01:02:31] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/issue-35677.stderr
[01:02:31] To update references, rerun the tests and pass the `--bless` flag
[01:02:31] To only update this specific test, also pass `--test-args issues/issue-35677.rs`
[01:02:31] error: 1 errors occurred comparing output.
[01:02:31] status: exit code: 1
[01:02:31] status: exit code: 1
[01:02:31] command: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/src/test/ui/issues/issue-35677.rs" "-Zthreads=1" "--target=x86_64-unknown-linux-gnu" "--error-format" "json" "-Zui-testing" "-C" "prefer-dynamic" "-o" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/a" "-Crpath" "-O" "-Zunstable-options" "-Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "-L" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issues/issue-35677/auxiliary" "-A" "unused"
[01:02:31] ------------------------------------------
[01:02:31] 
[01:02:31] ------------------------------------------
[01:02:31] stderr:
[01:02:31] stderr:
[01:02:31] ------------------------------------------
[01:02:31] {"message":"no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope","code":{"code":"E0599","explanation":"\nThis error occurs when a method is used on a type which doesn't implement it:\n\nErroneous code example:\n\n```compile_fail,E0599\nstruct Mouth;\n\nlet x = Mouth;\nx.chocolate(); // error: no method named `chocolate` found for type `Mouth`\n               //        in the current scope\n```\n"},"level":"error","spans":[{"file_name":"/checkout/src/test/ui/issues/issue-35677.rs","byte_start":106,"byte_end":115,"line_start":4,"line_end":4,"column_start":10,"column_end":19,"is_primary":true,"text":[{"text":"    this.is_subset(other)","highlight_start":10,"highlight_end":19}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the method `is_subset` exists but the following trait bounds were not satisfied:\n`T : std::cmp::Eq`\n`T : std::hash::Hash`","code":null,"level":"note","spans":[],"children":[],"rendered":null}],"rendered":"error[E0599]: no method named `is_subset` found for type `&std::collections::HashSet<T>` in the current scope\n  --> /checkout/src/test/ui/issues/issue-35677.rs:4:10\n   |\nLL |     this.is_subset(other)\n   |          ^^^^^^^^^\n   |\n   = note: the method `is_subset` exists but the following trait bounds were not satisfied:\n           `T : std::cmp::Eq`\n           `T : std::hash::Hash`\n\n"}
[01:02:31] {"message":"For more information about this error, try `rustc --explain E0599`.","code":null,"level":"","spans":[],"children":[],"rendered":"For more information about this error, try `rustc --explain E0599`.\n"}
[01:02:31] 
[01:02:31] ------------------------------------------
[01:02:31] 
---
[01:02:31] 
[01:02:31] thread 'main' panicked at 'Some tests failed', src/tools/compiletest/src/main.rs:496:22
[01:02:31] 
[01:02:31] 
[01:02:31] command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools-bin/compiletest" "--compile-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib" "--run-lib-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/x86_64-unknown-linux-gnu/lib" "--rustc-path" "/checkout/obj/build/x86_64-unknown-linux-gnu/stage2/bin/rustc" "--src-base" "/checkout/src/test/ui" "--build-base" "/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui" "--stage-id" "stage2-x86_64-unknown-linux-gnu" "--mode" "ui" "--target" "x86_64-unknown-linux-gnu" "--host" "x86_64-unknown-linux-gnu" "--llvm-filecheck" "/usr/lib/llvm-6.0/bin/FileCheck" "--host-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Zunstable-options  -Lnative=/checkout/obj/build/x86_64-unknown-linux-gnu/native/rust-test-helpers" "--docck-python" "/usr/bin/python2.7" "--lldb-python" "/usr/bin/python2.7" "--gdb" "/usr/bin/gdb" "--quiet" "--llvm-version" "6.0.0\n" "--system-llvm" "--cc" "" "--cxx" "" "--cflags" "" "--llvm-components" "" "--llvm-cxxflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"
[01:02:31] 
[01:02:31] 
[01:02:31] failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test
[01:02:31] Build completed unsuccessfully in 0:04:09
[01:02:31] Build completed unsuccessfully in 0:04:09
[01:02:31] make: *** [check] Error 1
[01:02:31] Makefile:48: recipe for target 'check' failed
141200 ./obj/build/bootstrap/debug/incremental/bootstrap-2ahv8almm435e
141200 ./obj/build/bootstrap/debug/incremental/bootstrap-2ahv8almm435e
141196 ./obj/build/bootstrap/debug/incremental/bootstrap-2ahv8almm435e/s-f9e7lytw3c-1ohh389-170x7pprjykmo
137092 ./obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release
134316 ./obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps
123292 ./src/llvm-project/llvm/test/CodeGen
108528 ./src/llvm-project/lldb

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

@Centril Centril added T-libs-api Relevant to the library API team, which will review and decide on the PR/issue. relnotes Marks issues that should be documented in the release notes of the next release. needs-fcp This change is insta-stable, so needs a completed FCP to proceed. labels Feb 11, 2019
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Amanieu commented Feb 11, 2019

Assuming the change for hasher is reverted.

@rfcbot fcp merge

@nox nox force-pushed the relax-bounds branch 3 times, most recently from 6879128 to 82fb122 Compare February 11, 2019 21:05
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Awesome! I just wanted this the other day 🙂

(Same kind of things as nox already mentioned: passed a &HashMap into a function, and was annoyed at how many bounds I had to add when it was clearly not even possible to modify it.)

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nox commented Feb 12, 2019

Pushed a commit that I didn't intend to push directly in that PR, but I guess maybe I should? I did a similar patch for BTreeMap<K, V>.

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nox commented Feb 12, 2019

Sorry, I meant BinaryHeap<T>.

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bors commented Feb 12, 2019

☔ The latest upstream changes (presumably #58341) made this pull request unmergeable. Please resolve the merge conflicts.

Notably, hash iterators don't require any trait bounds to be iterated.
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dtolnay commented Feb 14, 2019

@rfcbot reviewed

under the understanding that the set of API changes is:

  impl<K, V, S> HashMap<K, V, S>
- where
-     K: Eq + Hash,
-     S: BuildHasher,
  {
      fn capacity(&self) -> usize;
      fn keys(&self) -> Keys<K, V>;
      fn values(&self) -> Values<K, V>;
      fn values_mut(&mut self) -> ValuesMut<K, V>;
      fn iter(&self) -> Iter<K, V>;
      fn iter_mut(&mut self) -> IterMut<K, V>;
      fn len(&self) -> usize;
      fn is_empty(&self) -> bool;
      fn drain(&mut self) -> Drain<K, V>;
      fn clear(&mut self);
  }

  impl<'a, K, V, S> IntoIterator for &'a HashMap<K, V, S>
- where
-     K: Eq + Hash,
-     S: BuildHasher;

  impl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>
- where
-     K: Eq + Hash,
-     S: BuildHasher;

  impl<K, V, S> IntoIterator for HashMap<K, V, S>
- where
-     K: Eq + Hash,
-     S: BuildHasher;

  impl<T, S> HashSet<T, S>
- where
-     T: Eq + Hash,
-     S: BuildHasher,
  {
      fn capacity(&self) -> usize;
      fn iter(&self) -> Iter<T>;
      fn len(&self) -> usize;
      fn is_empty(&self) -> bool;
      fn drain(&mut self) -> Drain<T>;
      fn clear(&mut self);
  }

  impl<'a, T, S> IntoIterator for &'a HashSet<T, S>
- where
-     T: Eq + Hash,
-     S: BuildHasher;

  impl<T, S> IntoIterator for HashSet<T, S>
- where
-     T: Eq + Hash,
-     S: BuildHasher;

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dtolnay commented Feb 14, 2019

Is it possible that drain would want to shrink and rehash things?

Edit: never mind, this isn't like Vec::drain where there can be items left afterward.

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Currently HashMap and Vec never shrink implicitly, only when a dedicated method like shrink_to_fit is called. If the collection happens to grow again later, this saves on allocator traffic.

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rfcbot commented Feb 14, 2019

🔔 This is now entering its final comment period, as per the review above. 🔔

@rfcbot rfcbot added final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. and removed proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. labels Feb 14, 2019
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rfcbot commented Feb 24, 2019

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process,I would like to thank @sfacklerfor their work and everyone else who contributed.

The RFC will be merged soon.

@rfcbot rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Feb 24, 2019
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dtolnay commented Feb 25, 2019

@bors r+

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bors commented Feb 25, 2019

📌 Commit d9e2259 has been approved by dtolnay

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Feb 25, 2019
Centril added a commit to Centril/rust that referenced this pull request Feb 25, 2019
Relax some Hash bounds on HashMap<K, V, S> and HashSet<T, S>

Notably, hash iterators don't require any trait bounds to be iterated.
bors added a commit that referenced this pull request Feb 25, 2019
Rollup of 5 pull requests

Successful merges:

 - #58370 (Relax some Hash bounds on HashMap<K, V, S> and HashSet<T, S>)
 - #58421 (Relax some Ord bounds on BinaryHeap<T>)
 - #58686 (replace deprecated rustfmt_skip with rustfmt::skip)
 - #58697 (Use ? in some macros)
 - #58704 (Remove some unnecessary 'extern crate')

Failed merges:

r? @ghost
@bors bors merged commit d9e2259 into rust-lang:master Feb 25, 2019
netbsd-srcmastr pushed a commit to NetBSD/pkgsrc that referenced this pull request Apr 14, 2019
Pkgsrc changes:
 * Bump required rust version to build to 1.33.0.
 * Adapt patches to changed file locations.
 * (I worry about 32-bit ports, now that Atomic64 apparently is First-Class;
   this has been built on NetBSD/amd64 so far)

Upstream changes:

Version 1.34.0 (2019-04-11)
==========================

Language
--------
- [You can now use `#[deprecated = "reason"]`][58166] as a shorthand for
  `#[deprecated(note = "reason")]`. This was previously allowed by mistake
  but had no effect.
- [You can now accept token streams in `#[attr()]`,`#[attr[]]`, and
  `#[attr{}]` procedural macros.][57367]
- [You can now write `extern crate self as foo;`][57407] to import your
  crate's root into the extern prelude.


Compiler
--------
- [You can now target `riscv64imac-unknown-none-elf` and
  `riscv64gc-unknown-none-elf`.][58406]
- [You can now enable linker plugin LTO optimisations with
  `-C linker-plugin-lto`.][58057] This allows rustc to compile your Rust code
  into LLVM bitcode allowing LLVM to perform LTO optimisations across C/C++ FFI
  boundaries.
- [You can now target `powerpc64-unknown-freebsd`.][57809]


Libraries
---------
- [The trait bounds have been removed on some of `HashMap<K, V, S>`'s and
  `HashSet<T, S>`'s basic methods.][58370] Most notably you no longer require
  the `Hash` trait to create an iterator.
- [The `Ord` trait bounds have been removed on some of `BinaryHeap<T>`'s basic
  methods.][58421] Most notably you no longer require the `Ord` trait to create
  an iterator.
- [The methods `overflowing_neg` and `wrapping_neg` are now `const` functions
  for all numeric types.][58044]
- [Indexing a `str` is now generic over all types that
  implement `SliceIndex<str>`.][57604]
- [`str::trim`, `str::trim_matches`, `str::trim_{start, end}`, and
  `str::trim_{start, end}_matches` are now `#[must_use]`][57106] and will
  produce a warning if their returning type is unused.
- [The methods `checked_pow`, `saturating_pow`, `wrapping_pow`, and
  `overflowing_pow` are now available for all numeric types.][57873] These are
  equivalvent to methods such as `wrapping_add` for the `pow` operation.


Stabilized APIs
---------------

#### std & core
* [`Any::type_id`]
* [`Error::type_id`]
* [`atomic::AtomicI16`]
* [`atomic::AtomicI32`]
* [`atomic::AtomicI64`]
* [`atomic::AtomicI8`]
* [`atomic::AtomicU16`]
* [`atomic::AtomicU32`]
* [`atomic::AtomicU64`]
* [`atomic::AtomicU8`]
* [`convert::Infallible`]
* [`convert::TryFrom`]
* [`convert::TryInto`]
* [`iter::from_fn`]
* [`iter::successors`]
* [`num::NonZeroI128`]
* [`num::NonZeroI16`]
* [`num::NonZeroI32`]
* [`num::NonZeroI64`]
* [`num::NonZeroI8`]
* [`num::NonZeroIsize`]
* [`slice::sort_by_cached_key`]
* [`str::escape_debug`]
* [`str::escape_default`]
* [`str::escape_unicode`]
* [`str::split_ascii_whitespace`]

#### std
* [`Instant::checked_add`]
* [`Instant::checked_sub`]
* [`SystemTime::checked_add`]
* [`SystemTime::checked_sub`]

Cargo
-----
- [You can now use alternative registries to crates.io.][cargo/6654]

Misc
----
- [You can now use the `?` operator in your documentation tests without manually
  adding `fn main() -> Result<(), _> {}`.][56470]

Compatibility Notes
-------------------
- [`Command::before_exec` is now deprecated in favor of the
  unsafe method `Command::pre_exec`.][58059]
- [Use of `ATOMIC_{BOOL, ISIZE, USIZE}_INIT` is now deprecated.][57425] As you
  can now use `const` functions in `static` variables.

[58370]: rust-lang/rust#58370
[58406]: rust-lang/rust#58406
[58421]: rust-lang/rust#58421
[58166]: rust-lang/rust#58166
[58044]: rust-lang/rust#58044
[58057]: rust-lang/rust#58057
[58059]: rust-lang/rust#58059
[57809]: rust-lang/rust#57809
[57873]: rust-lang/rust#57873
[57604]: rust-lang/rust#57604
[57367]: rust-lang/rust#57367
[57407]: rust-lang/rust#57407
[57425]: rust-lang/rust#57425
[57106]: rust-lang/rust#57106
[56470]: rust-lang/rust#56470
[cargo/6654]: rust-lang/cargo#6654
[`Any::type_id`]: https://doc.rust-lang.org/std/any/trait.Any.html#tymethod.type_id
[`Error::type_id`]: https://doc.rust-lang.org/std/error/trait.Error.html#tymethod.type_id
[`atomic::AtomicI16`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI16.html
[`atomic::AtomicI32`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI32.html
[`atomic::AtomicI64`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI64.html
[`atomic::AtomicI8`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI8.html
[`atomic::AtomicU16`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU16.html
[`atomic::AtomicU32`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU32.html
[`atomic::AtomicU64`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU64.html
[`atomic::AtomicU8`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU8.html
[`convert::Infallible`]: https://doc.rust-lang.org/std/convert/enum.Infallible.html
[`convert::TryFrom`]: https://doc.rust-lang.org/std/convert/trait.TryFrom.html
[`convert::TryInto`]: https://doc.rust-lang.org/std/convert/trait.TryInto.html
[`iter::from_fn`]: https://doc.rust-lang.org/std/iter/fn.from_fn.html
[`iter::successors`]: https://doc.rust-lang.org/std/iter/fn.successors.html
[`num::NonZeroI128`]: https://doc.rust-lang.org/std/num/struct.NonZeroI128.html
[`num::NonZeroI16`]: https://doc.rust-lang.org/std/num/struct.NonZeroI16.html
[`num::NonZeroI32`]: https://doc.rust-lang.org/std/num/struct.NonZeroI32.html
[`num::NonZeroI64`]: https://doc.rust-lang.org/std/num/struct.NonZeroI64.html
[`num::NonZeroI8`]: https://doc.rust-lang.org/std/num/struct.NonZeroI8.html
[`num::NonZeroIsize`]: https://doc.rust-lang.org/std/num/struct.NonZeroIsize.html
[`slice::sort_by_cached_key`]: https://doc.rust-lang.org/std/slice/fn.sort_by_cached_key
[`str::escape_debug`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_debug
[`str::escape_default`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_default
[`str::escape_unicode`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_unicode
[`str::split_ascii_whitespace`]: https://doc.rust-lang.org/std/primitive.str.html#method.split_ascii_whitespace
[`Instant::checked_add`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_add
[`Instant::checked_sub`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_sub
[`SystemTime::checked_add`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_add
[`SystemTime::checked_sub`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_sub
@Centril Centril added this to the 1.34 milestone Apr 26, 2019
netbsd-srcmastr pushed a commit to NetBSD/pkgsrc that referenced this pull request May 19, 2019
Pkgsrc changes:
 * Bump required rust version to build to 1.33.0.
 * Adapt patches to changed file locations.
 * (I worry about 32-bit ports, now that Atomic64 apparently is First-Class;
   this has been built on NetBSD/amd64 so far)

Upstream changes:

Version 1.34.0 (2019-04-11)
==========================

Language
--------
- [You can now use `#[deprecated = "reason"]`][58166] as a shorthand for
  `#[deprecated(note = "reason")]`. This was previously allowed by mistake
  but had no effect.
- [You can now accept token streams in `#[attr()]`,`#[attr[]]`, and
  `#[attr{}]` procedural macros.][57367]
- [You can now write `extern crate self as foo;`][57407] to import your
  crate's root into the extern prelude.


Compiler
--------
- [You can now target `riscv64imac-unknown-none-elf` and
  `riscv64gc-unknown-none-elf`.][58406]
- [You can now enable linker plugin LTO optimisations with
  `-C linker-plugin-lto`.][58057] This allows rustc to compile your Rust code
  into LLVM bitcode allowing LLVM to perform LTO optimisations across C/C++ FFI
  boundaries.
- [You can now target `powerpc64-unknown-freebsd`.][57809]


Libraries
---------
- [The trait bounds have been removed on some of `HashMap<K, V, S>`'s and
  `HashSet<T, S>`'s basic methods.][58370] Most notably you no longer require
  the `Hash` trait to create an iterator.
- [The `Ord` trait bounds have been removed on some of `BinaryHeap<T>`'s basic
  methods.][58421] Most notably you no longer require the `Ord` trait to create
  an iterator.
- [The methods `overflowing_neg` and `wrapping_neg` are now `const` functions
  for all numeric types.][58044]
- [Indexing a `str` is now generic over all types that
  implement `SliceIndex<str>`.][57604]
- [`str::trim`, `str::trim_matches`, `str::trim_{start, end}`, and
  `str::trim_{start, end}_matches` are now `#[must_use]`][57106] and will
  produce a warning if their returning type is unused.
- [The methods `checked_pow`, `saturating_pow`, `wrapping_pow`, and
  `overflowing_pow` are now available for all numeric types.][57873] These are
  equivalvent to methods such as `wrapping_add` for the `pow` operation.


Stabilized APIs
---------------

#### std & core
* [`Any::type_id`]
* [`Error::type_id`]
* [`atomic::AtomicI16`]
* [`atomic::AtomicI32`]
* [`atomic::AtomicI64`]
* [`atomic::AtomicI8`]
* [`atomic::AtomicU16`]
* [`atomic::AtomicU32`]
* [`atomic::AtomicU64`]
* [`atomic::AtomicU8`]
* [`convert::Infallible`]
* [`convert::TryFrom`]
* [`convert::TryInto`]
* [`iter::from_fn`]
* [`iter::successors`]
* [`num::NonZeroI128`]
* [`num::NonZeroI16`]
* [`num::NonZeroI32`]
* [`num::NonZeroI64`]
* [`num::NonZeroI8`]
* [`num::NonZeroIsize`]
* [`slice::sort_by_cached_key`]
* [`str::escape_debug`]
* [`str::escape_default`]
* [`str::escape_unicode`]
* [`str::split_ascii_whitespace`]

#### std
* [`Instant::checked_add`]
* [`Instant::checked_sub`]
* [`SystemTime::checked_add`]
* [`SystemTime::checked_sub`]

Cargo
-----
- [You can now use alternative registries to crates.io.][cargo/6654]

Misc
----
- [You can now use the `?` operator in your documentation tests without manually
  adding `fn main() -> Result<(), _> {}`.][56470]

Compatibility Notes
-------------------
- [`Command::before_exec` is now deprecated in favor of the
  unsafe method `Command::pre_exec`.][58059]
- [Use of `ATOMIC_{BOOL, ISIZE, USIZE}_INIT` is now deprecated.][57425] As you
  can now use `const` functions in `static` variables.

[58370]: rust-lang/rust#58370
[58406]: rust-lang/rust#58406
[58421]: rust-lang/rust#58421
[58166]: rust-lang/rust#58166
[58044]: rust-lang/rust#58044
[58057]: rust-lang/rust#58057
[58059]: rust-lang/rust#58059
[57809]: rust-lang/rust#57809
[57873]: rust-lang/rust#57873
[57604]: rust-lang/rust#57604
[57367]: rust-lang/rust#57367
[57407]: rust-lang/rust#57407
[57425]: rust-lang/rust#57425
[57106]: rust-lang/rust#57106
[56470]: rust-lang/rust#56470
[cargo/6654]: rust-lang/cargo#6654
[`Any::type_id`]: https://doc.rust-lang.org/std/any/trait.Any.html#tymethod.type_id
[`Error::type_id`]: https://doc.rust-lang.org/std/error/trait.Error.html#tymethod.type_id
[`atomic::AtomicI16`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI16.html
[`atomic::AtomicI32`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI32.html
[`atomic::AtomicI64`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI64.html
[`atomic::AtomicI8`]: https://doc.rust-lang.org/std/atomic/struct.AtomicI8.html
[`atomic::AtomicU16`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU16.html
[`atomic::AtomicU32`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU32.html
[`atomic::AtomicU64`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU64.html
[`atomic::AtomicU8`]: https://doc.rust-lang.org/std/atomic/struct.AtomicU8.html
[`convert::Infallible`]: https://doc.rust-lang.org/std/convert/enum.Infallible.html
[`convert::TryFrom`]: https://doc.rust-lang.org/std/convert/trait.TryFrom.html
[`convert::TryInto`]: https://doc.rust-lang.org/std/convert/trait.TryInto.html
[`iter::from_fn`]: https://doc.rust-lang.org/std/iter/fn.from_fn.html
[`iter::successors`]: https://doc.rust-lang.org/std/iter/fn.successors.html
[`num::NonZeroI128`]: https://doc.rust-lang.org/std/num/struct.NonZeroI128.html
[`num::NonZeroI16`]: https://doc.rust-lang.org/std/num/struct.NonZeroI16.html
[`num::NonZeroI32`]: https://doc.rust-lang.org/std/num/struct.NonZeroI32.html
[`num::NonZeroI64`]: https://doc.rust-lang.org/std/num/struct.NonZeroI64.html
[`num::NonZeroI8`]: https://doc.rust-lang.org/std/num/struct.NonZeroI8.html
[`num::NonZeroIsize`]: https://doc.rust-lang.org/std/num/struct.NonZeroIsize.html
[`slice::sort_by_cached_key`]: https://doc.rust-lang.org/std/slice/fn.sort_by_cached_key
[`str::escape_debug`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_debug
[`str::escape_default`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_default
[`str::escape_unicode`]: https://doc.rust-lang.org/std/primitive.str.html#method.escape_unicode
[`str::split_ascii_whitespace`]: https://doc.rust-lang.org/std/primitive.str.html#method.split_ascii_whitespace
[`Instant::checked_add`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_add
[`Instant::checked_sub`]: https://doc.rust-lang.org/std/time/struct.Instant.html#method.checked_sub
[`SystemTime::checked_add`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_add
[`SystemTime::checked_sub`]: https://doc.rust-lang.org/std/time/struct.SystemTime.html#method.checked_sub
@dtolnay dtolnay assigned dtolnay and unassigned alexcrichton Mar 24, 2024
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