Implement new visitor

[mmun]

Implements a new visitor that fully traverses the AST. It was designed in the spirit of Babel's transform. Usage:

import { traverse } from "htmlbars-syntax";

let ast = parse(`{{name-tag name=(upcase user.name)}}`);

traverse(ast, {
  PathExpression(node) {
    console.log(node.original); // Logs "name-tag", "upcase", "user.name"
  }
});

Alternatively, you can use the enter/exit format to capture when the node is entered and exited:

import { traverse } from "htmlbars-syntax";

let ast = parse(`...`);
let depth = -1;

traverse(ast, {
  Program: {
    enter() { depth++; },
    exit() { depth--; }
  }
});

[mmun]

There are more features coming for this visitor:

• aliases (e.g. the Statement key is visited for any kind of Statement)
• replacement API (calling this.remove() or this.replace(nodes) inside the node handlers)
• control flow API (this.skip() and this this.break())

[mixonic]

Nice!!! :star: :star: :star: