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HashMap's docs can do a better job of explaining how to implement a hasher #71652

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steveklabnik opened this issue Apr 28, 2020 · 0 comments · Fixed by #71677
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HashMap's docs can do a better job of explaining how to implement a hasher #71652

steveklabnik opened this issue Apr 28, 2020 · 0 comments · Fixed by #71677
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@Mark-Simulacrum
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A-collections Area: `std::collection` A-docs Area: documentation for any part of the project, including the compiler, standard library, and tools C-bug Category: This is a bug.

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@steveklabnik
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The docs say:

The hashing algorithm can be replaced on a per-HashMap basis using the default, with_hasher, and with_capacity_and_hasher methods. Many alternative algorithms are available on crates.io, such as the fnv crate.

However, there isn't a mention of the Hasher trait. If you look at the docs for with_hasher, the type is just S. If you look at the struct definition, S = RandomState is all you get. You have to click to RandomState, and then see that it implements Hasher, to know what's going on.
@steveklabnik steveklabnik added A-docs Area: documentation for any part of the project, including the compiler, standard library, and tools C-bug Category: This is a bug. labels Apr 28, 2020
@jonas-schievink jonas-schievink added the A-collections Area: `std::collection` label Apr 28, 2020
@Mark-Simulacrum Mark-Simulacrum self-assigned this Apr 29, 2020
@Mark-Simulacrum Mark-Simulacrum mentioned this issue Apr 29, 2020
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Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this issue May 15, 2020
@Dylan-DPC
Rollup merge of rust-lang#71677 - Mark-Simulacrum:hasher-docs, r=Amanieu
91e693b 
Add explicit references to the BuildHasher trait

Fixes rust-lang#71652
Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this issue May 15, 2020
@Dylan-DPC
Rollup merge of rust-lang#71677 - Mark-Simulacrum:hasher-docs, r=Amanieu
592180c 
Add explicit references to the BuildHasher trait

Fixes rust-lang#71652
Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this issue May 15, 2020
@Dylan-DPC
Rollup merge of rust-lang#71677 - Mark-Simulacrum:hasher-docs, r=Amanieu
9f0e5c4 
Add explicit references to the BuildHasher trait

Fixes rust-lang#71652
@bors bors closed this as completed in 21d58a1 May 16, 2020
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A-collections Area: `std::collection` A-docs Area: documentation for any part of the project, including the compiler, standard library, and tools C-bug Category: This is a bug.
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Add explicit references to the BuildHasher trait Mark-Simulacrum/rust
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@steveklabnik @jonas-schievink @Mark-Simulacrum