Struct Annotations 

pub struct Annotations<'a, M> { /* private fields */ }

A collection of annotations attached to a Snippet.

Spans

Each annotation is a Range<usize> whose indices are positions in the snippet’s source unit sequence (as defined by the concrete Snippet implementation).

Spans are half-open: start is inclusive, end is exclusive. Zero-length spans (start == end) are allowed and render as a single caret pointing at that position.

Labels

A label is stored as a list of (String, M) fragments. This allows attaching different metadata to different parts of the label (for example, to highlight a keyword inside the label). If you do not need per-fragment metadata, you can use a single-element vector.

Empty label fragments are allowed; the renderer will simply output nothing for them (just the carets or connector lines of the annotation).

Example

See the crate-level documentation.

Implementations

impl<'a, M> Annotations<'a, M>

pub fn new(snippet: &'a Snippet, main_style: &'a MainStyle<M>) -> Self

Creates a new annotation collection for snippet.

pub fn add_annotation( &mut self, span: Range<usize>, style: &'a AnnotStyle<M>, label: Vec<(String, M)>, )

Adds an annotation span with the given style and label.

span is a half-open range (start inclusive, end exclusive) expressed in the snippet’s source units (see Annotations docs).

label is a list of text fragments with associated metadata; these fragments are concatenated when rendered.

pub fn max_line_no_width(&self) -> usize

pub fn render<O: Output<M>>( &self, max_line_no_width: usize, max_fill_after_first: usize, max_fill_before_last: usize, out: O, ) -> Result<(), O::Error>

Renders the snippet with the annotations.

If no annotations have been added, this outputs nothing.

max_line_no_width should be at least self.max_line_no_width(), but it can be greater to align vertically the margin of multiple snippets.

max_fill_after_first and max_fill_before_last control how many unannotated lines are rendered when there is a gap between two annotated lines:

• If the gap size is greater than max_fill_after_first + max_fill_before_last, the renderer outputs only the first max_fill_after_first lines after the previous annotated line, then a dotted separator line, then the last max_fill_before_last lines before the next annotated line.
• Otherwise, all lines in the gap are rendered.

Trait Implementations

impl<'a, M: Debug> Debug for Annotations<'a, M>

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

Formats the value using the given formatter.