import { Project } from 'projen';
/**
 * Return a value if the check value is truthy, undefined otherwise.
 */
export declare function ifSet(check: any, then: any): any;
/**
 * Return the list without undefined or null elements.
 */
export declare function noEmpties(list: any[]): any[];
type DeepPartial<T> = T extends object ? {
    [P in keyof T]?: DeepPartial<T[P]>;
} : T;
/**
 * Deep merge a user provided options object with defaults.
 * User options take precedence.
 */
export declare function deepDefaults<T>(options?: DeepPartial<T>, defaults?: DeepPartial<T>): T;
/**
 * Immutable deep merging objects.
 */
export declare function deepMerge(...data: any[]): any;
/**
 * Is this thing an object
 */
export declare function isObject(x: any): x is object;
/**
 * Is this thing a plain object (i.e. `{a: 1}`)
 */
export declare function isPlainObject(x: any): x is object;
/**
 * Middleware stack to set default options
 */
export declare function defaultOptions<T>(...middleware: OptionsMiddleware<T>[]): OptionsMiddleware<T>;
export type OptionsMiddleware<T> = (options: T) => any;
/**
 * Middleware stack to configure features
 */
export declare function configureFeatures<T extends Project = Project>(...middleware: FeatureMiddleware<T>[]): FeatureMiddleware<T>;
export type FeatureMiddleware<T extends Project = Project> = (project: T, options: any) => T;
export type Mutable<T> = {
    -readonly [P in keyof T]: T[P];
};
export {};