Lionel Henry

`vec_cast()` should preserve names

7

```r vec_cast(c(a = 1, b = 3), int()) #> [1] 1 3 ```

Once the semantics of `vec_is()` are fixed (#1687), explore whether we can improve performance of common type determination of the elements of homogeneous lists by using `vec_is()`.

Fix `vec_is()` by comparing ptypes

1

We could make `vec_is()` generic by requiring the result of `vec_ptype()` to only contain essential attributes. Methods for `vec_ptype()` would need to remove any details attributes. Ideally they'd just return...

Attributes should be sorted by tag before equality comparison

1

In practice attributes are an unordered type.

https://github.com/tidyverse/dplyr/issues/5339 from @billdenney

Add `vec_slice2()` and `vec_assign2()`

2

Branched from #1226. Following `vec_chop2()` and `vec_map()`, this further explores the idea of "extracting" variants of vctrs primitives. - With atomic vectors, `vec_slice2()` and `vec_assign2()` are equivalent to `vec_slice()` and...

Wrapper types

10

* `I()`. * haven-labelled: https://github.com/tidyverse/haven/pull/502. * Default `vctrs_vctr` subclasses: #968. * Feature request for a generic vctr class: #1162. * `omit` and `exclude`: #1160, #1179. * `table`: #1230.

Figure out composition of restore methods

2

Data frame restoration is currently weird because we first call restore-default, then dispatch on `vec_restore()`, which ends up calling restore-default again. I suspect it makes sense to automatically call restore...

Review convenience implementations for `vctrs_vctr`

5

Currently unclear what are the consequences of the special handling of `vctrs_vctr` classes. It makes me nervous that rcrds and list-ofs inherit from the current behaviour that I don't understand...