import { IContextFreeGrammarInput } from './types';
/**
 * Removes unreachable variables and production of a cfg
 * @param cfg Production rules, start variable and variables array of cfg
 * @returns A new production rule record and variables with unreachable variable and rules removed
 */
export declare function removeUnreachableProduction(inputCfg: Pick<IContextFreeGrammarInput, 'productionRules' | 'startVariable' | 'variables'>): string[];