pub trait RankQuad {
// Required methods
fn rank(&self, symbol: u8, i: usize) -> Option<usize>;
unsafe fn rank_unchecked(&self, symbol: u8, i: usize) -> usize;
}Expand description
A trait for the support of rank query over the alphabet [0..3].
Required Methods§
sourcefn rank(&self, symbol: u8, i: usize) -> Option<usize>
fn rank(&self, symbol: u8, i: usize) -> Option<usize>
Returns the number of occurrences in the indexed sequence of symbol up to
position i excluded. None if the position is out of bound.
sourceunsafe fn rank_unchecked(&self, symbol: u8, i: usize) -> usize
unsafe fn rank_unchecked(&self, symbol: u8, i: usize) -> usize
Returns the number of occurrences in the indexed sequence of symbol up to
position i excluded. The function does not check boundaries.
§Safety
Calling this method with an out-of-bounds index or with a symbol larger than 3 is undefined behavior.