Trait VisitAny

pub trait VisitAny<'ast, 'text: 'ast> {
    // Provided methods
    fn before(&mut self, _node: AnyNode<'ast, 'text>) { ... }
    fn after(&mut self, _node: AnyNode<'ast, 'text>) { ... }
}

The VisitAny trait is used to visit the AST without having to know the specific shape of each node. There are two methods, VisitAny::before and VisitAny::after, which are called before and after visiting the children of a given node, respectively.

The AnyNode enum is used to represent any node in the AST.

Example

use mf2_parser::ast::*;
use mf2_parser::VisitAny;
use mf2_parser::Visitable as _;
use mf2_parser::parse;

struct MyVisitor;

impl<'ast, 'text: 'ast> VisitAny<'ast, 'text> for MyVisitor {
  fn before(&mut self, node: AnyNode<'ast, 'text>) {
    println!("Start visiting node: {:?}", node);
  }

  fn after(&mut self, node: AnyNode<'ast, 'text>) {
    println!("Finished visiting node: {:?}", node);
  }
}

let (ast, _, _) = parse("Hello, {$name}!");
let mut visitor = MyVisitor;
ast.apply_visitor(&mut visitor);

Provided Methods

fn before(&mut self, _node: AnyNode<'ast, 'text>)

Called before visiting the children of a node.

The default implementation of this method does nothing.

fn after(&mut self, _node: AnyNode<'ast, 'text>)

Called after visiting the children of a node.

The default implementation of this method does nothing.

Implementors