import type { PgCodec, PgRegistry, PgResource, PgResourceParameter } from '@dataplan/pg';
/**
 * Whether a pgResource is a computed scalar attribute function, i.e. one that:
 * - takes at least one parameter,
 * - returns a scalar (its codec has no attributes),
 * - is unique (returns a single row),
 * - and takes a table row as its first parameter (that parameter's codec has
 *   attributes).
 *
 * Shared by the connection-filter and pg-aggregates plugins, which both need
 * to recognise computed columns exposed as functions.
 */
export declare function isComputedScalarAttributeResource(s: PgResource<any, any, any, any, any>): s is PgResource<string, PgCodec, never[], PgResourceParameter[], PgRegistry>;