jackfiled
3ed8bf5d36
All checks were successful
Run unit test / Unit-Test (push) Successful in 41s
Reviewed-on: https://git.bupt-hpc.cn/jackfiled/CanonSharp/pulls/2 Co-authored-by: jackfiled <xcrenchangjun@outlook.com> Co-committed-by: jackfiled <xcrenchangjun@outlook.com>
22 lines
986 B
C#
22 lines
986 B
C#
using CanonSharp.Combinator.Abstractions;
|
|
|
|
namespace CanonSharp.Combinator.Parsers.Modifiers;
|
|
|
|
/// <summary>
|
|
/// 向前看解析器
|
|
/// 使用传入的解析器向前解析
|
|
/// 但是返回的结果中输入流读取状态不前移
|
|
/// </summary>
|
|
/// <param name="parser">需要向前看的解析器</param>
|
|
/// <typeparam name="TToken">输入流令牌</typeparam>
|
|
/// <typeparam name="T">返回的解析结果类型</typeparam>
|
|
internal sealed class LookAheadParser<TToken, T>(Parser<TToken, T> parser) : ModifiedParser<TToken, T, T>(parser)
|
|
{
|
|
protected override ParseResult<TToken, T> Succeed<TState>(TState state,
|
|
SuccessfulResult<TToken, T> successfulResult)
|
|
=> ParseResultBuilder.Succeed<TToken, TState, T>(successfulResult.Value, state);
|
|
|
|
protected override ParseResult<TToken, T> Fail<TState>(TState state, FailedResult<TToken, T> failedResult)
|
|
=> ParseResultBuilder.Fail<TToken, TState, T>($"Failed when looking ahead: {failedResult}", state);
|
|
}
|