/**
 * @copyright Sister Software
 * @license AGPL-3.0
 * @author Teffen Ellis, et al.
 *
 *   Typed wrapper around `@dsnp/parquetjs`'s schema definition. Adds:
 *
 *   - `ParquetSchema<T>`: a generic class narrowing the base schema's `schema` property to a
 *       field-by-field typed dict.
 *   - `ParquetSchemaDefinitionCache`: an LRU lookup so hot paths that compute the same schema
 *       repeatedly pay the cost once. Implements `Disposable` so `using` works.
 *   - `createBloomFilters<T>`: helper that takes a schema and a list of columns and returns the
 *       `@dsnp/parquetjs`-shaped bloom-filter spec array.
 *
 *   `Symbol.dispose` is sync (the original was async, but `Disposable`'s contract is sync — async
 *   cleanup belongs on `AsyncDisposable`).
 */
import { ParquetSchema as BaseParquetSchema } from "@dsnp/parquetjs";
import type { createSBBFParams as BloomFilterCreation } from "@dsnp/parquetjs/dist/lib/bloomFilterIO/bloomFilterWriter.js";
import type { FieldDefinition } from "@dsnp/parquetjs/dist/lib/declare.js";
import { LRUCache } from "lru-cache";
/**
 * A Parquet record-like object, i.e. a record with string keys and JSON-serializable values.
 */
/**
 * Shape a row type must satisfy. Declare yours as a `type` alias — TypeScript gives an alias an implicit index
 * signature and an `interface` none, so an otherwise-identical interface does not satisfy this.
 */
export type ParquetRecordLike = Record<string, unknown | undefined>;
/**
 * Typed Parquet schema definition.
 */
export type ParquetSchemaDefinition<T = ParquetRecordLike> = Record<Extract<keyof T, string>, FieldDefinition>;
/**
 * Typed Parquet schema.
 */
export declare class ParquetSchema<T> extends BaseParquetSchema {
    schema: ParquetSchemaDefinition<T>;
}
/**
 * Given a Parquet schema and a list of columns, create a list of Bloom filters for those columns.
 */
export declare function createBloomFilters<T>(parquetSchemaDef: ParquetSchemaDefinition<T>, columns: Extract<keyof T, string>[]): BloomFilterCreation[];
export declare class ParquetSchemaDefinitionCache extends LRUCache<ParquetSchemaDefinition<ParquetRecordLike>, ParquetSchema<ParquetRecordLike>> implements Disposable {
    constructor(max?: number);
    findOrCreateSchema<T extends ParquetRecordLike>(schemaDef: ParquetSchemaDefinition<T>): ParquetSchema<T>;
    [Symbol.dispose](): void;
}
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