clarify BuilderHasherDefault summary

[tshepang]

This line is not clear:

A structure which implements BuildHasher for all Hasher types which also implement Default.

I don't know if BuilderHasherDefault implements BuilderHasher and Default for Hasher types, or if it implements BuilderHasher for Hasher types that themselves implement Default.

[steveklabnik]

@alexcrichton any thoughts on making the semantics here more clear? I'm not mega familiar with the Hash stuff.

[alexcrichton]

I was basically just attempting with words to describe the trait impls on BuildHasherDefault, but as @aturon was also confused by the wording I guess it definitely didn't get the point across!

[steveklabnik]

I would be happy to work with anyone who wants to work on this issue.

[adrianbrink]

@steveklabnik I would be glad to help out :-) What's the best way to start on this?

I am trying to find the source for the docs and I am ending up here, but somehow I think I am wrong.

[steveklabnik]

Hey @adrianbrink ! Thanks :)

That's the directory for all of the long-form docs. The API documentation is in the source. With this specific bit of docs, it's here:

rust/src/libcore/hash/mod.rs

Lines 251 to 255 in 9316ae5

	/// A structure which implements `BuildHasher` for all `Hasher` types which also
	/// implement `Default`.
	///
	/// This struct is 0-sized and does not need construction.
	#[stable(since = "1.7.0", feature = "build_hasher")]

So modifying these lines is where you need to go! Feel free to take a shot at it and just open a PR; we can workshop specific wording if you'd like in the PR itself. 😄

[frewsxcv]

Opened a PR for this: #38334.

[frewsxcv]

Oh sorry, I just realized now that it's tagged E-Easy. Had I noticed this earlier, I wouldn't have worked on it, sorry about that!