import { Tree } from '@angular-devkit/schematics';
/**
 * Adds a package to the package.json in the given tree
 */
export declare function addPackageToPackageJson(tree: Tree, pkg: string, version: string): Tree;
/**
 * Gets the version of the specified package by looking at the package.json in the given tree
 */
export declare function getPackageVersionFromPackageJson(tree: Tree, name: string): string | null;