using CanonSharp.Combinator.Abstractions; namespace CanonSharp.Combinator.Parsers.Modifiers; /// <summary> /// 尝试的解析器 /// 当成功时直接返回原结果 /// 当失败时调用resume函数处理失败结果并返回成功结果 /// </summary> /// <param name="parser">上游解析器</param> /// <param name="resume">处理失败结果的恢复函数</param> /// <typeparam name="TToken">输入流令牌</typeparam> /// <typeparam name="T">解析器返回结果类型</typeparam> internal sealed class TryParser<TToken, T>(IParser<TToken, T> parser, Func<IFailedResult<TToken, T>, T> resume) : ModifiedParser<TToken, T, T>(parser) { protected override IParseResult<TToken, T> Succeed<TState>(TState state, ISuccessfulResult<TToken, T> successfulResult) => successfulResult; protected override IParseResult<TToken, T> Fail<TState>(TState state, IFailedResult<TToken, T> failedResult) => ParseResultBuilder.Succeed<TToken, TState, T>(resume(failedResult), state); }