import { StateField } from '@codemirror/state';
import { BlockTreeIndex } from '../utils/block-index';
/** Effect to set the block tree index */
export declare const setBlockTreeIndexEffect: import('@codemirror/state').StateEffectType<BlockTreeIndex>;
/** StateField storing the block tree index */
export declare const blockTreeIndexField: StateField<BlockTreeIndex | null>;
/** Safe accessor */
export declare function getBlockTreeIndex(state: {
    field: <T>(f: StateField<T>) => T;
}): BlockTreeIndex | null;