Utility for determining whether an AST node is a reference.
foo is a reference in these cases:
console.log(foo);
var foo;
function foo() {}
function bar(foo) {}
export { foo as x };foo is not a reference in these cases:
var obj = { foo: 1 };
console.log(obj.foo);
export { x as foo };In all cases, foo is an Identifier node, but the two kinds must be treated differently for the purposes of scope analysis etc. (The examples are non-exhaustive.)
npm install is-referenceExample using Acorn and estree-walker:
import { parse } from 'acorn';
import { walk } from 'estree-walker';
import is_reference from 'is-reference';
const identifiers = [];
const references = [];
const ast = parse(`var a = b.c;`);
walk(ast, {
enter(node, parent) {
if (node.type === 'Identifier') identifiers.push(node);
if (is_reference(node, parent)) references.push(node);
}
});
identifiers.forEach(node => console.log(node.name)); // a, b, c
references.forEach(node => console.log(node.name)); // a, bMIT