/**
 * Check if string is not an empty string.
 *
 * @param	string The string to check.
 *
 * @returns	`true` if string is not empty, `false` otherwise.
 */
declare const isNotEmpty: (string: string) => boolean;
/**
 * Check if string is an empty string.
 *
 * @param	string The string to check.
 *
 * @returns	`true` if string is empty, `false` otherwise.
 */
declare const isEmpty: (string: string) => boolean;
/**
 * Check whether email is valid.
 *
 * @param	email The email to check.
 *
 * @returns `true` if the email is valid, `false` otherwise.
 */
declare const isValidEmail: (email: string) => boolean;
/**
 * Check whether phone number is valid.
 *
 * @param	phone The phone number to check.
 *
 * @supported
 *
 * - (123) 456-7890
 * - +(123) 456-7890
 * - +(123)-456-7890
 * - +(123) - 456-7890
 * - +(123) - 456-78-90
 * - 123-456-7890
 * - 123.456.7890
 * - 1234567890
 * - +393204567890
 * - +39 320 456 7890
 * - 00393204567890
 * - 075-63546725
 *
 * @returns `true` if the phone number is valid, `false` otherwise.
 */
declare const isValidPhoneNumber: (phone: string) => boolean;
/**
 * Check whether the given string is a valid VAT number.
 * @param	s The string to test.
 * @returns	`true` if the given string is a valid VAT number, `false` otherwise.
 */
declare const isValidVat: (s: string) => boolean;
/**
 * Check if value is less then another value.
 *
 * @param	a		The number being compared.
 * @param	value	The value to compare.
 *
 * @returns	`true` if given `value` is less than `a`, `false` otherwise.
 */
declare const isLessThan: (a: number, value?: number | string) => boolean;
/**
 * Check if value is greater then another value.
 *
 * @param	a		The number being compared.
 * @param	value	The value to compare.
 *
 * @returns	`true` if given `value` is greater than `a`, `false` otherwise.
 */
declare const isGreaterThan: (a: number, value?: number | string) => boolean;
/**
 * Check if value is in a range of two values.
 *
 * @param	a		The minimum value.
 * @param	b		The maximum value.
 * @param	value	The value to compare.
 *
 * @returns	`true` if given `value` is equal or greather than `a` and equal or less than `b`, `false` otherwise.
 */
declare const isInRange: (a: number, b: number, value?: number | string) => boolean;
/**
 * Check whether value `a` is equal to `b`.
 *
 * @param	a The first value to check.
 * @param	b The second value to check.
 *
 * @returns `true` if `a` and `b` are equal, `false` otherwise.
 */
declare const isStrictEqual: (a: unknown, b: unknown) => boolean;
/**
 * Detect if input contains SQL statements.
 *
 * @param	value The value to check.
 * @returns	`true` if value contains SQL statements, `false` otherwise.
 */
declare const isSQLStatement: (value: any) => boolean;

export { isEmpty, isGreaterThan, isInRange, isLessThan, isNotEmpty, isSQLStatement, isStrictEqual, isValidEmail, isValidPhoneNumber, isValidVat };