Struct LineNumbers 

pub struct LineNumbers {
    pub line_starts: Vec<u32>,
    pub length: u32,
    pub mapping: HashMap<usize, CharLen>,
}

A struct which contains information about line numbers of a source file, and can convert between byte offsets that are used in the compiler and line-column pairs used in LSP.

Fields

line_starts: Vec<u32>

The byte offsets of the start of each line of the source file

length: u32

The total length of the source file

mapping: HashMap<usize, CharLen>

A mapping of byte offsets to character length information. This is used when converting between byte indices and line-column numbers, because LSP uses UTF-16, while Rust encodes strings as UTF-8.

This only contains characters which are more than one byte in UTF-8, because one byte UTF-8 characters are one UTF-16 segment also, so no translation is needed.

We could store the whole source file here instead, however that would be quite wasteful. Most Gleam programs use only ASCII characters, meaning UTF-8 offsets are the same as UTF-16 ones. With this representation, we only need to store a few characters.

In most programs this will be empty because they will only be using ASCII characters.

Implementations

impl LineNumbers

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

pub fn line_number(&self, byte_index: u32) -> u32

Returns the 0-indexed line number of a given byte index

pub fn line_and_column_number(&self, byte_index: u32) -> LineColumn

Returns the line and column of a given byte index.

pub fn byte_index_of_line_col(&self, position: LineColumn) -> u32

Returns the starting byte index of a Unicode code point at a given line and column.

pub fn spans_entire_line(&self, span: &Span) -> bool

Checks if the given span spans an entire line (excluding the newline character itself).

pub fn span_of_range(&self, range: &Range, source_id: u16) -> Span

Converts a Range of some source file to a Span.

pub fn range_of_span(&self, span: Span) -> Range

Converts a Span to a Range.

Trait Implementations

impl Clone for LineNumbers

fn clone(&self) -> LineNumbers

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LineNumbers

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

Formats the value using the given formatter.

impl PartialEq for LineNumbers

fn eq(&self, other: &LineNumbers) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for LineNumbers

impl StructuralPartialEq for LineNumbers