Struct Overlay 

pub struct Overlay {
    pub handle: OverlayHandle,
    pub namespace: Option<OverlayNamespace>,
    pub start_marker: MarkerId,
    pub end_marker: MarkerId,
    pub face: OverlayFace,
    pub priority: Priority,
    pub message: Option<String>,
    pub extend_to_line_end: bool,
    pub url: Option<String>,
    pub theme_key: Option<&'static str>,
}

An overlay represents a visual decoration over a range of text Uses markers for content-anchored positions that automatically adjust with edits

Fields

handle: OverlayHandle

Unique handle for this overlay (opaque, for removal by handle)

namespace: Option<OverlayNamespace>

Namespace this overlay belongs to (for bulk removal)

start_marker: MarkerId

Start marker (left affinity - stays before inserted text)

end_marker: MarkerId

End marker (right affinity - moves after inserted text)

face: OverlayFace

Visual appearance of the overlay

priority: Priority

Priority for z-ordering (higher = on top)

message: Option<String>

Optional tooltip/message to show when hovering over this overlay

extend_to_line_end: bool

Whether to extend the overlay’s background to the end of the visual line Used for full-width line highlighting (e.g., in diff views)

url: Option<String>

Optional URL for OSC 8 terminal hyperlinks. When set, the rendered text in this overlay becomes a clickable hyperlink.

theme_key: Option<&'static str>

Theme key that produced this overlay’s primary color (e.g. “diagnostic.warning_bg”). Recorded at creation time so the theme inspector can show the exact key without reverse-mapping colors.

Implementations

impl Overlay

pub fn new( marker_list: &mut MarkerList, range: Range<usize>, face: OverlayFace, ) -> Self

Create a new overlay with markers at the given range

Arguments

• marker_list - MarkerList to create markers in
• range - Byte range for the overlay
• face - Visual appearance

Returns the overlay (which contains its handle for later removal)

pub fn with_namespace( marker_list: &mut MarkerList, range: Range<usize>, face: OverlayFace, namespace: OverlayNamespace, ) -> Self

Create an overlay with a namespace (for bulk removal)

pub fn with_priority( marker_list: &mut MarkerList, range: Range<usize>, face: OverlayFace, priority: Priority, ) -> Self

Create an overlay with a specific priority

pub fn with_message(self, message: String) -> Self

Add a message/tooltip to this overlay

pub fn with_priority_value(self, priority: Priority) -> Self

Set the priority

pub fn with_namespace_value(self, namespace: OverlayNamespace) -> Self

Set the namespace

pub fn with_extend_to_line_end(self, extend: bool) -> Self

Set whether to extend the overlay to the end of the visual line

pub fn with_theme_key(self, key: &'static str) -> Self

Set the theme key that produced this overlay’s color

pub fn range(&self, marker_list: &MarkerList) -> Range<usize>

Get the current byte range by resolving markers This is called once per frame during rendering setup

pub fn contains(&self, position: usize, marker_list: &MarkerList) -> bool

Check if this overlay contains a position

pub fn overlaps(&self, range: &Range<usize>, marker_list: &MarkerList) -> bool

Check if this overlay overlaps with a range

impl Overlay

Helper functions for creating common overlay types

pub fn error( marker_list: &mut MarkerList, range: Range<usize>, message: Option<String>, ) -> Self

Create an error underline overlay (wavy red line)

pub fn warning( marker_list: &mut MarkerList, range: Range<usize>, message: Option<String>, ) -> Self

Create a warning underline overlay (wavy yellow line)

pub fn info( marker_list: &mut MarkerList, range: Range<usize>, message: Option<String>, ) -> Self

Create an info underline overlay (wavy blue line)

pub fn hint( marker_list: &mut MarkerList, range: Range<usize>, message: Option<String>, ) -> Self

Create a hint underline overlay (dotted gray line)

pub fn selection(marker_list: &mut MarkerList, range: Range<usize>) -> Self

Create a selection highlight overlay

pub fn search_match(marker_list: &mut MarkerList, range: Range<usize>) -> Self

Create a search result highlight overlay

Trait Implementations

impl Clone for Overlay

fn clone(&self) -> Overlay

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Overlay

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

Formats the value using the given formatter.