通过解析库探究函数式抽象代价 ( ini 解析示例补充)

BenchmarkDotNet v0.13.12, Windows 11 (10.0.22631.3085/23H2/2023Update/SunValley3)Intel Core i7-9750H CPU 2.60GHz, 1 CPU, 12 logical and 6 physical cores.NET SDK 8.0.200  [Host]     : .NET 8.0.2 (8.0.224.6711), X64 RyuJIT AVX2  DefaultJob : .NET 8.0.2 (8.0.224.6711), X64 RyuJIT AVX2

// * Legends *  Mean      : Arithmetic mean of all measurements  Error     : Half of 99.9% confidence interval  StdDev    : Standard deviation of all measurements  Gen0      : GC Generation 0 collects per 1000 operations  Gen1      : GC Generation 1 collects per 1000 operations  Allocated : Allocated memory per single operation (managed only, inclusive, 1KB = 1024B)  1 ns      : 1 Nanosecond (0.000000001 sec)

public static IDictionary<string, string?> Read(string content){    var data = new Dictionary<string, string?>(StringComparer.OrdinalIgnoreCase);    using (var reader = new StringReader(content))    {        string sectionPrefix = string.Empty;
        while (reader.Peek() != -1)        {            string rawLine = reader.ReadLine()!; // Since Peak didn't return -1, stream hasn't ended.            string line = rawLine.Trim();
            // Ignore blank lines            if (string.IsNullOrWhiteSpace(line))            {                continue;            }            // Ignore comments            if (line[0] is ';' or '#' or '/')            {                continue;            }            // [Section:header]            if (line[0] == '[' && line[line.Length - 1] == ']')            {                // remove the brackets                sectionPrefix = string.Concat(line.AsSpan(1, line.Length - 2).Trim(), ConfigurationPath.KeyDelimiter);                continue;            }
            // key = value OR "value"            int separator = line.IndexOf('=');            if (separator < 0)            {                throw new FormatException(rawLine);            }
            string key = sectionPrefix + line.Substring(0, separator).Trim();            string value = line.Substring(separator + 1).Trim();
            // Remove quotes            if (value.Length > 1 && value[0] == '"' && value[value.Length - 1] == '"')            {                value = value.Substring(1, value.Length - 2);            }
            if (data.ContainsKey(key))            {                throw new FormatException(key);            }
            data[key] = value;        }    }    return data;}

public class Ini{    private static Ini instance = new Ini();
    public Func<IPeeker<char>, bool> WhiteSpace = Chars.IngoreWhiteSpace.Map(i => i > 0);
    public Func<IPeeker<char>, bool> Comment = Chars.In(";#/").Delimited(Chars.NotCRLF.ToSlice().Opt(), Chars.IsCRLF, "Comment not right").Map((c, x, y, z) => c);
    public Func<IPeeker<char>, string> SectionName = Chars.Is('[').Delimited(Chars.Not(']').ToSlice().Once("Section name is required."), Chars.Is(']'), "Section name must end with ']'").Map((c, x, y, z) => y?.ToString());
    public Func<IPeeker<char>, string> Key = Chars.Not('=').ToSlice().Once("key is required.").Map(i => i.ToString());    public Func<IPeeker<char>, char> Separater = Chars.Is('=').Once("Section name is required.");
    public Func<IPeeker<char>, string> Value = Chars.NotCRLF.ToSlice().Once("value is required.").Map(i =>    {        var v = i.ToString().Trim();        return v.StartsWith('"') ? v[1..^1] : v;    });
    public IDictionary<string, string> ParseString(string content)    {        var input = Input.From(content);        var dict = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);        while (input.TryPeek(out var v))        {            if (!(WhiteSpace(input) || Comment(input) || Section(input, dict)))            {                throw new NotSupportedException(v.ToString());            }        }        return dict;    }
    public bool SectionContentEnd(IPeeker<char> input)    {        return !input.TryPeek(out var v) || v is '[';    }
    public bool Section(StringPeeker input, Dictionary<string, string> dict)    {        var name = SectionName(input);        if (name == null) return false;        while (!SectionContentEnd(input))        {            if (WhiteSpace(input) || Comment(input))            {                continue;            }            SectionKV(input, dict, name);        }        return true;    }
    public void SectionKV(StringPeeker input, Dictionary<string, string> dict, string name)    {        var k = Key(input);        Separater(input);        var v = Value(input);        k = $"{name}:{k.Trim()}";        dict.Add(k, v.Trim());    }
    public static IDictionary<string, string> Parse(string content)    {        return instance.ParseString(content);    }}

public IniData Parse(string iniDataString){    IniData iniData = (Configuration.CaseInsensitive ? new IniDataCaseInsensitive() : new IniData());    iniData.Configuration = Configuration.Clone();    if (string.IsNullOrEmpty(iniDataString))    {        return iniData;    }
    _errorExceptions.Clear();    _currentCommentListTemp.Clear();    _currentSectionNameTemp = null;    try    {        string[] array = iniDataString.Split(new string[2] { "\n", "\r\n" }, StringSplitOptions.None);        for (int i = 0; i < array.Length; i++)        {            string text = array[i];            if (text.Trim() == string.Empty)            {                continue;            }
            try            {                ProcessLine(text, iniData);            }            catch (Exception ex)            {                ParsingException ex2 = new ParsingException(ex.Message, i + 1, text, ex);                if (Configuration.ThrowExceptionsOnError)                {                    throw ex2;                }
                _errorExceptions.Add(ex2);            }        }
        if (_currentCommentListTemp.Count > 0)        {            if (iniData.Sections.Count > 0)            {                iniData.Sections.GetSectionData(_currentSectionNameTemp).TrailingComments.AddRange(_currentCommentListTemp);            }            else if (iniData.Global.Count > 0)            {                iniData.Global.GetLast().Comments.AddRange(_currentCommentListTemp);            }
            _currentCommentListTemp.Clear();        }    }    catch (Exception item)    {        _errorExceptions.Add(item);        if (Configuration.ThrowExceptionsOnError)        {            throw;        }    }
    if (HasError)    {        return null;    }
    return (IniData)iniData.Clone();}