Struct Frontmatter 

pub struct Frontmatter { /* private fields */ }

Ordered list of frontmatter items with map-keyed convenience accessors.

Top-level YAML comments live in items as FrontmatterItem::Comment. Comments inside nested mappings/sequences live in nested_comments, keyed by structural path; the emitter re-injects them at the matching position when serialising the value tree.

Implementations

impl Frontmatter

pub fn new() -> Self

Create an empty Frontmatter.

pub fn from_index_map(map: IndexMap<String, QuillValue>) -> Self

Build from an IndexMap of fields (no comments, no fill markers).

pub fn from_items(items: Vec<FrontmatterItem>) -> Self

Build from a pre-computed item list.

pub fn from_items_with_nested( items: Vec<FrontmatterItem>, nested_comments: Vec<NestedComment>, ) -> Self

Build from a pre-computed item list and a set of nested comments.

pub fn nested_comments(&self) -> &[NestedComment]

Comments captured inside nested mappings/sequences. The emitter re-injects these at the matching position when serialising the value tree.

pub fn items(&self) -> &[FrontmatterItem]

Ordered iterator over raw items (including comments).

pub fn iter(&self) -> impl Iterator<Item = (&String, &QuillValue)> + '_

Iterator over (key, value) pairs, skipping comments. Preserves order.

pub fn keys(&self) -> impl Iterator<Item = &String> + '_

Iterator over field keys, skipping comments. Preserves order.

pub fn len(&self) -> usize

Number of field items (comments excluded).

pub fn is_empty(&self) -> bool

Returns true if there are no field items (comments are ignored).

pub fn get(&self, key: &str) -> Option<&QuillValue>

Look up a field value by key.

pub fn contains_key(&self, key: &str) -> bool

Returns true if a field with this key is present.

pub fn insert( &mut self, key: impl Into<String>, value: QuillValue, ) -> Option<QuillValue>

Insert or update a field. Always clears the fill marker (field is no longer a placeholder). Preserves position for existing keys; appends new keys at the end. Adjacent comments are untouched.

pub fn insert_fill( &mut self, key: impl Into<String>, value: QuillValue, ) -> Option<QuillValue>

Insert or update a field and mark it as a !fill placeholder. Preserves position for existing keys; appends new keys at the end.

pub fn remove(&mut self, key: &str) -> Option<QuillValue>

Remove a field by key and return its value. Adjacent comments stay where they are.

pub fn is_fill(&self, key: &str) -> bool

Returns true if a field with this key is marked !fill.

pub fn to_index_map(&self) -> IndexMap<String, QuillValue>

Project the field portion into an IndexMap<String, QuillValue>. Comments are dropped; fill markers are lost. Preserves order.

Trait Implementations

impl Clone for Frontmatter

fn clone(&self) -> Frontmatter

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Frontmatter

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

Formats the value using the given formatter.

impl Default for Frontmatter

fn default() -> Frontmatter

Returns the “default value” for a type.

impl<'a> IntoIterator for &'a Frontmatter

type Item = (&'a String, &'a QuillValue)

The type of the elements being iterated over.

type IntoIter = FilterMap<Iter<'a, FrontmatterItem>, fn(&'a FrontmatterItem) -> Option<(&'a String, &'a QuillValue)>>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl PartialEq for Frontmatter

fn eq(&self, other: &Frontmatter) -> 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 StructuralPartialEq for Frontmatter