import deepCopy from 'rfdc';
import deepMerge from 'deepmerge';
import { JsonValue } from '../types';
/**
 * Validate a possible JSON object represented as string
 */
export declare function isJSONObjectString(s: string): boolean;
/**
 * Validate a possible JSON object represented as string
 */
export declare function isJSONObject(o: any): boolean;
export declare function isValidJSON(v: any): v is JsonValue;
/**
 * Cast a value to a type (bypasses similarity check)
 * @param value - Pass value to cast or leave empty to create an empty type-only placeholder
 */
export declare const cast: <T>(value?: any) => T;
/**
 * Swap key & value in a map
 */
export declare const reverseMap: <TKeyType, TValType>(map: Map<TKeyType, TValType>) => Map<TValType, TKeyType>;
/**
 * forEach with accumulator. This is meant to replace difficult to read Array.reduce methods.
 */
export declare function accForEach<T, Acc>(arr: T[], acc: Acc, cb: (item: T, acc: Acc, index: number, arr: T[]) => void): Acc;
/**
 * forEach with accumulator. This is meant to replace difficult to read Array.reduce methods.
 */
export declare function accForEach<T, Acc>(iterable: Iterable<T>, acc: Acc, cb: (item: T, acc: Acc, index: number, iterable: Iterable<T>) => void): Acc;
/**
 * Executes fn, swallowing error (saves performance by not generating a stack)
 */
export declare function swallowError<Fn extends (...args: any[]) => any, ErrRetVal = undefined>(fn: Fn, errorReturnValue?: ErrRetVal): ReturnType<Fn> | ErrRetVal;
/**
 * If value is truthy, returns `value` (or `v` if no `value` provided), otherwise, returns an empty string
 * @param v - Var to check for truthiness
 * @param value - Value to return if true
 */
export declare function truthyStr(v: any, value?: string): string;
/**
 * Join paths with forward separator (ignores falsy) & normalizes (all backslashes to forward slash, no running slashes)
 */
export declare function normalizeAndJoinPaths(...paths: (string | undefined)[]): string;
export { deepMerge, deepCopy };