/**
 * Resolving a machine slug when the tree is only half-translated.
 *
 * `machine(slug:, language:)` resolves a slug ONLY in the language that slug
 * was authored in. `language` is also mandatory (omitting it is a validation
 * error, not a wildcard) and case-sensitive — `'nl'` misses where `'NL'` hits.
 *
 * That matters because the listing no longer narrows to one language: an
 * installation authored only in NL now appears in an EN tree and is linked by
 * its NL slug (PWP-993). Following that link then asked for
 * `machine(slug: "<NL slug>", language: "EN")`, which the API answers with
 * `SPARE_PARTS_MACHINE_NOT_FOUND_ERROR` — so the row came back but the page
 * behind it was empty, with a title derived from the slug and no error. The bug
 * moved one click deeper instead of going away.
 *
 * The URL carries no language, so the only thing a cold deep link can do is try
 * the languages the shop actually uses. `machine(id:)` is language-agnostic,
 * but an id is not what a shareable URL contains.
 */
/** Is this the API saying the slug/language pair does not exist? */
export declare function isMachineNotFound(error: unknown): boolean;
/**
 * The languages to try, in order: the tree language first (the common case and
 * the only one that costs a request in a fully-translated shop), then the
 * storefront language, then any others the host declares.
 *
 * Upper-cased and de-duplicated — the API matches the case exactly.
 */
export declare function machineLanguageCandidates(machineLanguage: string | undefined, language: string | undefined, extra: string[] | undefined): string[];
/**
 * Call `fetchOne` with each candidate language until one resolves.
 *
 * Returns `null` when every candidate reported "not found" — that is a real
 * answer (the slug exists in no language we know of), and the caller should say
 * so rather than render an empty listing. Any OTHER failure is rethrown
 * immediately: a network blip or an auth error must not be retried three times
 * and then reported as a missing machine.
 */
export declare function resolveMachineAcrossLanguages<T>(candidates: string[], fetchOne: (language: string) => Promise<T | null | undefined>): Promise<{
    machine: T;
    language: string;
} | null>;