import { Injector, Block } from './injector';
import { IteratorBlock, RenderItemsGetter } from './iterate';
import { MountBlock, Scope } from './types';
import { Component } from './component';
declare type KeyExpr = (host: Component, scope?: Scope) => string;
interface ItemLookup {
    [key: string]: KeyIteratorItemBlock;
}
interface KeyIteratorBlock extends IteratorBlock {
    keyExpr: KeyExpr;
    used: ItemLookup | null;
    rendered: ItemLookup | null;
    order: KeyIteratorItemBlock[];
    needReorder: boolean;
    parentScope: Scope;
}
interface KeyIteratorItemBlock extends Block {
    next: this | null;
}
/**
 * Renders key iterator block
 */
export declare function mountKeyIterator(host: Component, injector: Injector, get: RenderItemsGetter, keyExpr: KeyExpr, body: MountBlock): KeyIteratorBlock;
/**
 * Updates iterator block defined in `ctx`
 * @returns Returns `1` if iterator was updated, `0` otherwise
 */
export declare function updateKeyIterator(block: KeyIteratorBlock): number;
export declare function unmountKeyIterator(block: KeyIteratorBlock): void;
export declare function clearKeyIterator(block: KeyIteratorBlock): void;
export {};