Function syntect::util::split_at

pub fn split_at<'a, A: Clone>(
    v: &[(A, &'a str)], 
    split_i: usize
) -> (Vec<(A, &'a str)>, Vec<(A, &'a str)>)

Split a highlighted line at a byte index in the line into a before and after component. It's just a helper that does the somewhat tricky logic including splitting a span if the index lies on a boundary.

This can be used to extract a chunk of the line out for special treatment like wrapping it in an HTML tag for extra styling.

Generic for testing purposes and fancier use cases, but intended for use with the Vec<(Style, &str)> returned by highlight methods. Look at the source code for modify_range for an example usage.