Struct LineIndex 

pub struct LineIndex { /* private fields */ }

A per-snapshot table of line-start byte offsets, built once and shared by every position lookup over that snapshot (#732).

line_col scans from byte 0 on every call, so emitting n positions over an n-byte snapshot is O(n²). This precomputes the byte offset where each line begins; a lookup binary-searches for the line (O(log n)) and then counts columns only within that one line. Consumers that map many spans per request — semantic tokens, folding ranges, diagnostics, inlay hints, document symbols, the emit source map — build one of these per snapshot and reuse it.

Implementations

impl LineIndex

pub fn new(source: &str) -> Self

Precompute the line-start table for source in one O(n) pass.

pub fn line(&self, offset: usize) -> usize

0-based line containing offset, by binary search over the line starts.

pub fn line_start(&self, line: usize) -> usize

Byte offset where the 0-based line begins.

pub fn line_col(&self, source: &str, offset: usize) -> (usize, usize)

1-indexed (line, column) of offset, columns counting characters — identical to line_col but O(log n + line length) after the one-time build. source must be the same string the index was built from.

pub fn utf16_line_col(&self, source: &str, offset: usize) -> (u32, u32)

0-based (line, UTF-16 column) of offset — the LSP default position encoding (columns count UTF-16 code units, so a 4-byte astral char is 2). source must be the same string the index was built from.

Trait Implementations

impl Clone for LineIndex

fn clone(&self) -> LineIndex

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LineIndex

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.