line-numbers

line-numbers is a Rust crate for efficiently finding the line number of a string offset.

Usage

Create a LinePositions, then you can find line numbers for an offset.

let s = "foo\nbar\nbaz\n";
let s_lines: Vec<_> = s.lines().collect();

let line_positions = LinePositions::from(s);

let offset = 5;
let (line_num, column) = line_positions.from_offset(offset);

println!(
    "Offset {} is on line {} (column {}), and the text of that line is {:?}.",
    offset,
    line_num.display(),
    column,
    s_lines[line_num.as_usize()]
);

Similar Projects

• line-span solves a similar problem, but scans the whole string every time.