Be consistent with `Keys` and `Values` iterators

[gankra]

Be consistent with `Keys` and `Values` iterators

[reem]

I believe the current (IMO annoying :P) convention is to use newtypes.

[Gankra]

@aturon has plans for some kind of macro to make this more ergonomic.

But yeah, annoying.

[Gankra]

Strictly speaking we could not bother since we make no back-compat guarantees at all.

[aturon]

@gankro I believe a few such macros are currently in use in std for this purpose.

[aturon]

(I think it'd be interesting to try to provide a robust form of these macros in crates.io, but I won't have time to do that myself any time soon.)

[apasel422]

Is there even a reason to have these iterators? Adaptors provide the same functionality without the combinatoric explosion of key-value/mutable-immutable/forward-reverse/subrange variants.

[Gankra]

Hmm... I... Don't disagree.

[tbu-]

You're making the intent clearer if you ask for keys or values only – also there's the possibility of implementing "just getting the keys" in a more efficient way, because it doesn't have to touch the values.

[reem]

Ideally there's a way to get a keys iterator that doesn't contain the values type - this has been a problem for me in the past.

Thanks,
Jonathan Reem

On Wed, Jan 28, 2015 at 12:26 PM, tbu- [email protected] wrote:

You're making the intent clearer if you ask for keys or values only – also there's the possibility of implementing "just getting the keys" in a more efficient way, because it doesn't have to touch the values.

Reply to this email directly or view it on GitHub:
#99 (comment)

[apasel422]

@reem As written, both forms (type alias and wrapper struct) reference the value type. Without being space-inefficient or using trait objects or unsafe code, I don't see how they can be written without being parameterized over the value.

[reem]

Depending on the data structure it is sometimes possible to do it unsafely.

Thanks,
Jonathan Reem

On Wed, Jan 28, 2015 at 12:38 PM, Andrew Paseltiner
[email protected] wrote:

@reem As written, both forms (type alias and wrapper struct) reference the value type. Without being space-inefficient or using trait objects or unsafe code, I don't see how they can be written without being parameterized over the value.

Reply to this email directly or view it on GitHub:
#99 (comment)

[apasel422]

Closing because trie is now in an external crate. CC contain-rs/trie#4.