import type { Comment, ReturnStatement, SourceLocation } from 'estree';
import type { StepperExpression, StepperPattern } from '..';
import { StepperBaseNode } from '../../interface';
import type { RedexInfo } from '../..';
export declare class StepperReturnStatement extends StepperBaseNode<ReturnStatement> implements ReturnStatement {
    readonly argument: StepperExpression | null;
    constructor(argument: StepperExpression | null, leadingComments?: Comment[] | undefined, trailingComments?: Comment[] | undefined, loc?: SourceLocation | null | undefined, range?: [number, number] | undefined);
    static create(node: ReturnStatement): StepperReturnStatement;
    isContractible(): boolean;
    isOneStepPossible(): boolean;
    contract(redex: RedexInfo): StepperExpression;
    contractEmpty(redex: RedexInfo): void;
    oneStep(redex: RedexInfo): StepperExpression;
    substitute(id: StepperPattern, value: StepperExpression, redex: RedexInfo): StepperBaseNode;
    freeNames(): string[];
    allNames(): string[];
    rename(before: string, after: string): StepperReturnStatement;
}