Struct rowan::GreenNodeBuilder

pub struct GreenNodeBuilder { /* fields omitted */ }

A builder for a green tree.

Methods

impl GreenNodeBuilder

pub fn new() -> GreenNodeBuilder

Creates new builder.

pub fn token(&mut self, kind: SyntaxKind, text: SmolStr)

Adds new token to the current branch.

pub fn start_node(&mut self, kind: SyntaxKind)

Start new node and make it current.

pub fn finish_node(&mut self)

Finish current branch and restore previous branch as current.

pub fn checkpoint(&self) -> Checkpoint

Prepare for maybe wrapping the next node. The way wrapping works is that you first of all get a checkpoint, then you place all tokens you want to wrap, and then maybe call start_node_at. Example:

let checkpoint = builder.checkpoint();
parser.parse_expr();
if parser.peek() == Some(PLUS) {
  // 1 + 2 = Add(1, 2)
  builder.start_node_at(checkpoint, OPERATION);
  parser.parse_expr();
  builder.finish_node();
}

pub fn start_node_at(&mut self, checkpoint: Checkpoint, kind: SyntaxKind)

Wrap the previous branch marked by checkpoint in a new branch and make it current.

pub fn finish(self) -> GreenNode

Complete tree building. Make sure that start_node_at and finish_node calls are paired!

Trait Implementations

impl Default for GreenNodeBuilder

fn default() -> GreenNodeBuilder

Returns the "default value" for a type.

impl Debug for GreenNodeBuilder

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

Formats the value using the given formatter.