/**
 * Shared warning for the optional external-formatter post-pass that every
 * language driver runs when `emitTarget.format !== false` (the default).
 *
 * The formatter is optional — deterministic emitter output is always the
 * fallback — but its *presence* changes the emitted bytes, so a silently
 * swallowed failure turns host-dependent drift into an un-attributable
 * investigation. Emitting a loud, greppable Warning keeps the drift traceable
 * (regen gates can grep for it) while never failing the emit.
 */
export declare function formatFormatterWarning(tool: string, dir: string, error: unknown): string;
/** Log {@link formatFormatterWarning} to stderr via `console.warn`. */
export declare function warnFormatterUnavailable(tool: string, dir: string, error: unknown): void;
/**
 * Warning for a consumer-declared formatter whose installed version does not
 * satisfy the pinned `version` in the target's `format` spec.
 *
 * Kept non-fatal and loud, matching {@link formatFormatterWarning}: a version
 * skew still formats the tree, but the greppable warning makes any resulting
 * byte drift attributable to the toolchain rather than the emitter.
 */
export declare function formatFormatterVersionMismatch(tool: string, expected: string, actual: string | null): string;
/** Log {@link formatFormatterVersionMismatch} to stderr via `console.warn`. */
export declare function warnFormatterVersionMismatch(tool: string, expected: string, actual: string | null): void;