/**
 * Adds a space character before non-consecutive capital letters
 */
declare function decamel(str: string): string;

interface OptionProperties {
    style: string;
    currency: string;
    minimumFractionDigits: number;
}
interface Options {
    locales: "en-US";
    options: OptionProperties;
}
interface formattedCurrency {
    currency: string;
    integer: string;
    separator: string;
    decimal: string;
    fraction: string;
}
declare function formatCurrency(amount: number, options?: Options): formattedCurrency;

declare type ArgTypes = undefined | null | string | number | Array<any> | Record<any, any>;
declare function isNil(arg: ArgTypes): boolean;

declare function isObject(arg: any): boolean;

/**
 * @param {any}
 *
 * @returns {Array[string, string]} [Typeof instance, if it has mutable methods]
 */
declare function instanceOfBuiltin(arg: any): [string, string];

declare type MapKey = string | number;
/**
 * WARNING: TypeScript doesn't catch when a map key is a non-"MapKey" type
 */
declare function mapToObject(m: Map<MapKey, unknown>): Record<string, unknown>;

declare type NormalizeStringReturn = [string, Error | null];
/**
 * normalizeString trims surrounding white space and replaces duplicate white space with a single space
 */
declare function normalizeString(input: string): NormalizeStringReturn;

declare function objectToString<T>(arg: T, pad?: string, indention?: string): string;

/**
 * Safe JSON parse
 * If the param string is valid JSON, safeJSONParse returns the parsed JSON and null for the error value
 *
 * If the param string is *not* valid JSON, safeJSONParse returns the original string and an error message to let the consumer know it is not valid JSON
 */
declare type SafeJSONParseReturn = [Record<any, any> | any[] | string, Error | null];
declare function safeJSONParse(str: string): SafeJSONParseReturn;

declare function slugify(str: string): [string, Error | null];

declare function splitRunes(string: string): string[];

declare type StripEmojiReturn = [string, Error | null];
declare function stripEmojis(str: string): StripEmojiReturn;

declare function struct(obj: any): any;
declare function set(props: any): void;

declare type ToUpperCaseReturn = [string, Error | null];
/**
 * toUpperCase capitalizes the first letter of all the words in a string
 */
declare function toUpperCase(input: string): ToUpperCaseReturn;

declare function unsafeStripHTML(markup: string): string;

declare const wait: (ms?: number) => Promise<void>;

export { MapKey, decamel, formatCurrency, formattedCurrency, instanceOfBuiltin, isNil, isObject, mapToObject, normalizeString, objectToString, safeJSONParse, set, slugify, splitRunes, stripEmojis, struct, toUpperCase, unsafeStripHTML, wait };