Struct ElementGraph 

pub struct ElementGraph { /* private fields */ }

Index-based graph of relationships between document elements.

Built from a &[Element] slice, the graph stores parent/child and next/prev relationships as indices into the original slice. No ownership is taken and no lifetimes are introduced — the graph is a standalone value that can be stored, cloned, or sent across threads independently of the elements.

Example

use oxidize_pdf::parser::PdfDocument;
use oxidize_pdf::pipeline::ElementGraph;

let doc = PdfDocument::open("document.pdf")?;
let (elements, graph) = doc.partition_graph(Default::default())?;

for title_idx in graph.top_level_sections() {
    println!("Section: {}", elements[title_idx].text());
    for &child_idx in graph.children_of(title_idx) {
        println!("  {}", elements[child_idx].text());
    }
}

Parent / child semantics

An element at index i is a child of the nearest preceding Title element whose text matches elements[i].metadata().parent_heading. A Title element whose own parent_heading equals its own text is treated as a root (no parent) unless a different preceding title has the same text.

Implementations

impl ElementGraph

pub fn build(elements: &[Element]) -> Self

Build a graph from a slice of elements.

pub fn len(&self) -> usize

Number of elements in the graph (equals the length of the source slice).

pub fn is_empty(&self) -> bool

Returns true when the graph was built from an empty slice.

pub fn parent_of(&self, idx: usize) -> Option<usize>

Returns the index of the parent element of idx, or None if it is a root.

Panics

Panics if idx >= self.len().

pub fn children_of(&self, idx: usize) -> &[usize]

Returns the indices of the children of element idx.

Panics

Panics if idx >= self.len().

pub fn next_of(&self, idx: usize) -> Option<usize>

Returns the index of the element immediately after idx, or None if idx is the last element.

Panics

Panics if idx >= self.len().

pub fn prev_of(&self, idx: usize) -> Option<usize>

Returns the index of the element immediately before idx, or None if idx is the first element.

Panics

Panics if idx >= self.len().

pub fn elements_in_section(&self, title_idx: usize) -> Vec<usize>

Returns the child indices of a Title element (i.e., the elements belonging to its section).

This is an alias for children_of with a semantically clearer name for the common case of iterating a document section.

pub fn top_level_sections(&self) -> Vec<usize>

Returns the indices of all Title elements that have no parent (top-level sections).