import { FunctionDefinition, GraphNodeDefinition, VariableType } from "../types.js";
import { TypeCheckerContext } from "./types.js";
export declare function inferReturnTypes(ctx: TypeCheckerContext): void;
export declare function inferReturnTypeFor(name: string, def: FunctionDefinition | GraphNodeDefinition, ctx: TypeCheckerContext): VariableType;
/**
 * Build a union of distinct types (deduped structurally via a Map keyed by
 * the stringified shape). Returns the lone type when there's only one unique
 * entry, avoiding wrapping single types in a one-element union.
 */
export declare function unionTypes(types: VariableType[]): VariableType;