My second post

2022-11-10

TODO (Gains!!) TODO (Explanation of library + foreshadowing)

After poking around a bit, I found this function

fn bsearch_range_table(c: char, r: &[(char, char)]) -> bool {
    use core::cmp::Ordering::{Equal, Greater, Less};

    r.binary_search_by(|&(lo, hi)| {
        // Because ASCII ranges are at the start of the tables, a search for an
        // ASCII char will involve more `Greater` results (i.e. the `(lo,hi)`
        // table entry is greater than `c`) than `Less` results. And given that
        // ASCII chars are so common, it makes sense to favor them. Therefore,
        // the `Greater` case is tested for before the `Less` case.
        if lo > c {
            Greater
        } else if hi < c {
            Less
        } else {
            Equal
        }
    })
    .is_ok()
}

This uses the standard library's implementation of binary search. All standard library methods are marked as rust #[inline(always)], so I figured the compiler might see this and figure it's too large to inline.