| # Bit-Slice Indexing |
| |
| This trait, like its mirror in `core`, unifies various types that can be used to |
| index within a bit-slice. Individual `usize` indices can refer to exactly one |
| bit within a bit-slice, and `R: RangeBounds<usize>` ranges can refer to |
| subslices of any length within a bit-slice. |
| |
| The three operations (get, get unchecked, and index) reflect the three theories |
| of lookup within a collection: fallible, pre-checked, and crashing on failure. |
| |
| You will likely not use this trait directly; its methods all have corresponding |
| methods on [`BitSlice`] that delegate to particular implementations of it. |
| |
| ## Original |
| |
| [`slice::SliceIndex`](core::slice::SliceIndex) |
| |
| ## API Differences |
| |
| The [`SliceIndex::Output`] type is not usable here, because `bitvec` cannot |
| manifest a `&mut bool` reference. Work to unify referential values in the trait |
| system is ongoing, and in the future this functionality *may* be approximated. |
| |
| Instead, this uses two output types, [`Immut`] and [`Mut`], that are the |
| referential structures produced by indexing immutably or mutably, respectively. |
| This allows the range implementations to produce `&/mut BitSlice` as expected, |
| while `usize` produces the proxy structure. |
| |
| [`Immut`]: Self::Immut |
| [`Mut`]: Self::Mut |
| [`SliceIndex::Output`]: core::slice::SliceIndex::Output |
