/**
 * This module annotates the AST with the following information:
 *
 * 1. All scopeable nodes are annotated with a set of free identifiers.
 * 2. All function and program nodes are annotated with the set of
 *    free identifiers in their enclosing functions.
 */
import * as t from 'babel-types';
import { NodePath } from 'babel-traverse';
export interface NestedFunctionFree {
    nestedFunctionFree: Set<string>;
}
export declare function annotate(path: NodePath<t.Node>): void;
export declare function enclosingFunction(path: NodePath<t.Node>): NodePath<(t.Function | t.Program) & NestedFunctionFree>;
export declare function isNestedFree(path: NodePath<t.Function | t.Program>, x: string): boolean;