import execa from 'execa';
import { InstallConfig } from './config';
import { PackageList, Packages } from './types';
export declare function getPackageList(packages: Packages): PackageList;
export declare function getExecaConfig(config: InstallConfig): execa.CommonOptions;
/**
 * Error class used for cases that can't be reached. It's a helper for TypeScript
 */
export declare class UnreachableCaseError extends Error {
    constructor(val: never);
}