/**
 * Role-name routing for the core transform.
 *
 * Two databases can express the *same* access model with *different* role
 * names — one calls the unauthenticated role `anonymous`, another `anon`; one
 * calls the privileged role `administrator`, another something else. Portable
 * SQL must be able to translate role identifiers between these conventions.
 *
 * Scope, deliberately narrow: a {@link RoleRouter} only renames role
 * *identifiers* in the AST positions where a role name legitimately appears
 * (grants, ownership, policies, default privileges, role membership, role
 * settings). It does **not** alter role *attributes* (`BYPASSRLS`, `LOGIN`,
 * ...): two roles that share a name across conventions do not necessarily
 * share privilege scope, and inventing attribute changes would silently
 * misrepresent the security model. Privilege-semantics reconciliation is a
 * downstream, policy-level concern; the router restricts itself to the
 * deterministic, reversible part — the name.
 *
 * Renaming is a pure identifier substitution, so a router is trivially
 * invertible ({@link RoleRouter.invert}) for bidirectional translation.
 */
/** Role-rename specification: source role name -> target role name. */
export type RoleRouteSpec = Record<string, string>;
/** Resolves a target role name for a source role name. */
export declare class RoleRouter {
    private readonly map;
    constructor(routes?: RoleRouteSpec | Map<string, string>);
    /** Coerce a spec, map, or existing router into a router. */
    static from(source: RoleRouter | RoleRouteSpec | Map<string, string>): RoleRouter;
    /** Number of configured renames. */
    get size(): number;
    /**
     * Resolve the target name for `role`, or `undefined` when it is not routed
     * or already at its destination.
     */
    resolve(role: string | undefined | null): string | undefined;
    /**
     * The inverse router (target -> source), for translating in the opposite
     * direction. Throws if the mapping is not one-to-one.
     */
    invert(): RoleRouter;
}