/**
 * The declared type of an output column: `type="int64"`, `type="double|null"`,
 * `type="decimal(18,2)|null"` on a named `<data>`.
 *
 * Pure parsing of the attribute into a structured type. The mapping onto a
 * concrete container (Parquet physical + logical type) lives with that writer —
 * this layer is format-agnostic, so a future Arrow/Avro writer reuses it.
 * Spec: docs/specs/2026-07-19-typed-output-and-parquet-writer.md §2.
 */
export declare const COLUMN_KINDS: readonly ["bool", "int32", "int64", "uint8", "uint16", "uint32", "uint64", "float", "float16", "double", "string", "enum", "date", "timestamp", "decimal", "uuid", "json"];
export type ColumnKind = (typeof COLUMN_KINDS)[number];
export interface ColumnType {
    readonly kind: ColumnKind;
    /** `|null` — the column may hold NULL (Parquet OPTIONAL). */
    readonly nullable: boolean;
    /** decimal only: total digits. */
    readonly precision?: number;
    /** decimal only: digits after the point. */
    readonly scale?: number;
}
/**
 * A LIST column: `type="[]int64"`, or `type="[]int64|null"` where the `|null`
 * binds to the ELEMENT (read left to right: "a list of (int64 or nothing)").
 * That binding is what `missing=` on a repeating generator needs — it blanks
 * individual elements, never the list as a whole.
 *
 * There is no nullable LIST: an empty cell is an empty list, and we have no way
 * to express "no list at all", so we do not pretend to.
 */
export interface ListColumnType {
    readonly kind: 'list';
    readonly element: ColumnType;
}
/**
 * A MAP column: `type="{}int64"`, or `type="{}int64|null"` where the `|null`
 * binds to the VALUE — the same left-to-right reading a list has ("a map to
 * (int64 or nothing)").
 *
 * The KEY is always text. Parquet requires map keys to be non-null, and a cell
 * arrives here as text anyway, so a second type parameter would buy a
 * conversion nobody asked for and a syntax twice as wide.
 *
 * There is no nullable MAP, for the reason a list has none: an empty cell is an
 * empty map, and there is no way to say "no map at all".
 */
export interface MapColumnType {
    readonly kind: 'map';
    readonly value: ColumnType;
}
export type OutputColumnType = ColumnType | ListColumnType | MapColumnType;
export declare function isListType(type: OutputColumnType): type is ListColumnType;
export declare function isMapType(type: OutputColumnType): type is MapColumnType;
/** A list or a map — the shapes that hold several values in one cell. */
export declare function isRepeatedType(type: OutputColumnType): boolean;
/**
 * Parse a `type="…"` that may be a list. Everything else defers to
 * `parseColumnType`, so scalar behaviour is untouched.
 */
export declare function parseOutputColumnType(raw: string): OutputColumnType;
/** Parse a `type="…"` attribute. Throws with a user-facing message on bad input. */
export declare function parseColumnType(raw: string): ColumnType;
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