/** Remove `(?:)` token separators (most likely added by flag x) in cases where it's safe to do so. @param {string} expression @returns {PluginResult} */ export function clean(expression: string): PluginResult; export function flagXPreprocessor(value: import("./regex.js").InterpolatedValue, runningContext: import("./utils.js").RunningContext, options: Required): { transformed: string; runningContext: import("./utils.js").RunningContext; }; import type { PluginResult } from './regex.js';