import type { AgAggregationFunction } from '../api/agAggregationFunction';
import type { AgFieldIdentifier } from '../api/agField';
import type { AgStudioFieldIdentifier } from '../api/engine/agStudioQuery';
/** Composite identity key — output of `buildFieldKey`. Used as the column-map key throughout the engine. */
export type FieldKey = string & {
    readonly __brand: 'FieldKey';
};
/** Data source identifier (e.g. `'orders'`, `'products'`). */
export type SourceId = string & {
    readonly __brand: 'SourceId';
};
/**
 * Canonically construct the composite `FieldKey` for a field.
 *
 * Every slot is rendered, even when empty, so the shape is always
 * `sourceId$...$alias$...$fieldId$...$agg$...$det$...`. Empty optional
 * values produce consecutive separators (e.g. `$alias$$`).
 */
export declare function buildFieldKey(sourceId: string, fieldId: AgStudioFieldIdentifier, sourceAlias?: string, aggregation?: AgAggregationFunction, determinant?: string): FieldKey;
/**
 * Treat a bare `fieldId` as a `FieldKey`. Valid for un-aggregated fields
 * where the fieldId alone is the identity — expression dependency columns,
 * un-aggregated source fields in scan nodes, and window output fields.
 * Do NOT use for aggregated fields; use `buildFieldKey` with the
 * aggregation parameter instead.
 */
export declare function fieldIdAsKey(id: AgFieldIdentifier): FieldKey;