/**
 * Names that start with two underscores belong to the compiler and runtime:
 * `__matchval_1`, `__ctx`, `__self`. A user program may neither declare nor
 * read one. See `docs/dev/language/reserved-names.md`.
 */
/** The prefix template hygiene gives a renamed variable: `__hyg3_tmp`. */
export declare const HYGIENE_PREFIX = "__hyg";
/** Whether a user program is forbidden from using `name`. */
export declare function isReservedInternalName(name: string): boolean;
export declare function reservedInternalNameMessage(name: string): string;