import type { TypeAliasEntry, VariableType } from "../types.js";
/**
 * Canonical structural identity for a type — THE replacement for raw
 * `JSON.stringify(t)` at identity sites (uniteTypes, loop widening, union
 * dedup in synthesis, coinduction pair keys). Fixes the gaps raw stringify
 * had (issue #473): property-order sensitivity, non-semantic metadata
 * leaking into the key, and unresolved top-level aliases keying
 * differently from their bodies.
 *
 * Deliberate identity decisions (all safe because the consumers feed
 * dedup/diagnostics and cycle detection, never codegen schemas):
 * - The TOP node resolves ONE step via safeResolveType (recursive
 *   self-refs stay nominal via its guard); NESTED alias refs key
 *   nominally as `alias:Name` — never expanded, so recursion terminates
 *   and same-name refs always key equal.
 * - `valueArgs` ARE identity: `Age(18)` and `Age(21)` are different types.
 * - `tags`, `trivia`, property `description`s, `loc`, `isEffectSet`, and
 *   `blockType.raises` are NOT identity: two types differing only in
 *   annotations/formatting dedup together (first member's metadata wins
 *   at union joins — acceptable for diagnostics).
 * - Union members sort by canonical form (`A | B` keys equal `B | A`);
 *   object properties sort by key.
 */
export declare function typeKey(t: VariableType, aliases: Record<string, TypeAliasEntry>): string;