/**
 * XML utility functions
 */
/**
 * Escape special XML characters for safe TwiML embedding.
 *
 * Covers all five XML predefined entities. Apostrophes are included because
 * escaped values are also interpolated into attributes, and an attribute
 * delimited with single quotes would otherwise be terminated early.
 * `&` must be replaced first so the entities emitted below are not re-escaped.
 */
export declare function escapeXml(text: string): string;