/**
 * AST visitor to hoist WITH clauses out of UNION and other set operations.
 *
 * Drizzle can emit SQL like:
 *   (with a as (...) select ...) union (with b as (...) select ...)
 *
 * DuckDB 1.4.x has an internal binder bug for this pattern.
 * We merge per arm CTEs into a single top level WITH when names do not collide.
 *
 * Hoisting is skipped when it would change the query:
 * - an arm has ORDER BY, LIMIT or OFFSET, since the merged form drops the
 *   parentheses that scope those clauses to the arm
 * - a CTE name matches a table referenced by another arm, since the hoisted
 *   CTE would shadow that table
 *
 * When any arm uses WITH RECURSIVE, the merged WITH is RECURSIVE. That is
 * skipped when a CTE from a plain WITH reads a table of its own name.
 */
import type { AST } from 'node-sql-parser';
export declare function hoistUnionWith(ast: AST | AST[]): boolean;