/* 0.26.0-alpha2 */
/**
 * Return true if the string is a valid identifier.
 *
 * Check for identifiers matching a profile of [Unicode UAX31](https://unicode.org/reports/tr31/)
 *
 * See https://cortexjs.io/math-json/#identifiers for a full definition of the
 * profile.
 */
export declare function isValidIdentifier(s: string): boolean;
export declare const EMOJIS: RegExp;
export declare function validateIdentifier(s: unknown): 'valid' | 'not-a-string' | 'empty-string' | 'expected-nfc' | 'unexpected-mixed-emoji' | 'unexpected-bidi-marker' | 'unexpected-script' | 'invalid-first-char' | 'invalid-char';