Sample traversal of Espree AST

var estraverse = require('estraverse');
var fs = require('fs');

fs.readFile('./ast.json', 'utf-8', function(err, ast) {
	if(err) throw err;
	const data = JSON.parse(ast);
	estraverse.traverse(data, {
		enter: function(node, parent) {
			if(node.type === "Literal" && parent.type === "ArrayExpression") {
				if(!Number.isInteger(node.value)){
					// stop traversal when a Literal is not a number 
					return estraverse.VisitorOption.Break;
				}
			}
		},
		leave: function(node, parent) {
			//nothing for now
		}
	});
});