Struct Graph 

pub struct Graph { /* private fields */ }

A collection of named JSON documents that can be queried together via the v2 VM.

Thread safety

Graph is Send + Sync (nodes are plain serde_json::Value). The internal VM is not Sync, so wrap in Mutex for concurrent use.

Implementations

impl Graph

pub fn new() -> Self

Create an empty graph with a fresh VM.

pub fn with_capacity(compile_cap: usize, resolution_cap: usize) -> Self

Create a graph backed by a VM with custom capacity hints.

compile_cap — compile-cache slots; resolution_cap — resolution-cache slots.

pub fn add_node<S: Into<String>>(&mut self, name: S, value: Value) -> &mut Self

Add (or replace) a named node. Returns &mut self for chaining.

pub fn get_node(&self, name: &str) -> Option<&Value>

Return a reference to a node value, if it exists.

pub fn remove_node(&mut self, name: &str) -> Option<Value>

Remove a node, returning its value if it existed.

pub fn len(&self) -> usize

Return the number of nodes in the graph.

pub fn is_empty(&self) -> bool

Return true if the graph has no nodes.

pub fn node_names(&self) -> impl Iterator<Item = &str>

Return an iterator over node names.

pub fn query(&mut self, expr: &str) -> Result<Value, GraphError>

Evaluate a v2 expression against the virtual root — a JSON object { "node_name": value, ... } containing all nodes.

Navigate into a node via $.node_name....

pub fn query_node( &mut self, node: &str, expr: &str, ) -> Result<Value, GraphError>

Evaluate a v2 expression against a single named node directly.

pub fn register_method( &mut self, name: impl Into<String>, method: impl Method + 'static, )

Register a custom method callable from query expressions.

pub fn vm(&self) -> &VM

Access the underlying VM (e.g. to inspect cache stats).

pub fn vm_mut(&mut self) -> &mut VM

Mutable access to the underlying VM.

pub fn virtual_root(&self) -> Value

Build the virtual root object containing all nodes as top-level fields.

pub fn message(&mut self, schema: &str) -> Result<Value, GraphError>

Alias for query — reads better when constructing message schemas.

graph.message(r#"{ "total": $.orders.sum(price), "count": $.orders.len() }"#)

Trait Implementations

impl Default for Graph

fn default() -> Self

Returns the “default value” for a type.