export interface BiomeExtendsIndex {
    extendsTransitively(descendant: string, ancestor: string): boolean;
    readonly directTargets: ReadonlyMap<string, ReadonlySet<string>>;
}
export declare function buildBiomeExtendsIndex(scanRoots: readonly string[]): BiomeExtendsIndex;
export type ExtendsPrecedence = 'keep-existing' | 'replace' | 'conflict';
export declare function resolveExtendsPrecedence(index: BiomeExtendsIndex, existingBiomeId: string, incomingBiomeId: string): ExtendsPrecedence;
export declare function dedupeBySlugWithExtends<T>(items: readonly T[], opts: {
    readonly index: BiomeExtendsIndex;
    readonly slugOf: (item: T) => string;
    readonly biomeIdOf: (item: T) => string;
    readonly onConflict: (slug: string, existing: T, incoming: T) => never;
}): T[];
//# sourceMappingURL=extends-precedence.d.ts.map