export declare function isValidString(input: string, allowedChars?: string): boolean;
export declare function stringToArray(value: string | string[]): string[];
/**
 * Truncates an ethereum address to the format 0x0000…0000
 * @param address Full address to truncate
 * @returns Truncated address
 */
export declare function truncateEthAddress(address: string): string;
export declare function toProperCase(str: string): string;