/**
 * Kern Template Engine — dynamic pattern support
 *
 * Users define reusable code patterns in .kern files with typed slots.
 * Templates are registered at config/CLI time, then expanded during codegen.
 */
import { type KernRuntime } from './runtime.js';
import type { IRNode, TemplateDefinition } from './types.js';
export declare class KernTemplateError extends Error {
    constructor(message: string);
}
/**
 * Register a template from a parsed 'template' IRNode.
 * Extracts slot definitions, import declarations, and body from children.
 */
export declare function registerTemplate(node: IRNode, sourceFile?: string): void;
/** Check if a node type matches a registered template. */
export declare function isTemplateNode(type: string, runtime?: KernRuntime): boolean;
/** Clear all registered templates (for test isolation). */
export declare function clearTemplates(): void;
/** Get a registered template definition by name. */
export declare function getTemplate(name: string): TemplateDefinition | undefined;
/** Get count of registered templates. */
export declare function templateCount(): number;
/**
 * Expand a template instance node into TypeScript lines.
 *
 * Looks up the template definition by `node.type`, validates required slots against
 * `node.props`, replaces `{{slotName}}` placeholders, handles `{{CHILDREN}}` recursion,
 * and prepends import lines.
 *
 * @param node - IR node whose `type` matches a registered template name
 * @param _depth - Internal recursion depth counter (do not set manually)
 * @param runtime - Optional KernRuntime instance
 * @returns Array of generated TypeScript source lines
 * @throws {KernTemplateError} If expansion depth exceeds 10 (recursion guard)
 *   or required slots are missing
 */
export declare function expandTemplateNode(node: IRNode, _depth?: number, runtime?: KernRuntime): string[];