Use ubuntu for the CI

Eliminate various string allocations

.github/workflows/ci.yml

@@ -11,25 +11,24 @@ on:
 
 jobs:
   build:
-    runs-on: windows-latest
+    runs-on: ubuntu-latest
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         submodules: true
         fetch-depth: 0
 
-    - name: Install .NET 6.0, 7.0, and 8.0
-      uses: actions/setup-dotnet@v1
+    - name: Install .NET 6.0, and 8.0
+      uses: actions/setup-dotnet@v4
       with:
         dotnet-version: |
           6.0.x
-          7.0.x
           8.0.x
 
     - name: Build, Test, Pack, Publish
       shell: bash
       run: |
-        dotnet tool install -g dotnet-releaser
+        dotnet tool install -g dotnet-releaser --configfile .github/workflows/nuget_org_only.config
         dotnet-releaser run --nuget-token "${{secrets.NUGET_TOKEN}}" --github-token "${{secrets.GITHUB_TOKEN}}" src/dotnet-releaser.toml

.github/workflows/nuget_org_only.config

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageSources>
+    <clear />
+    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
+  </packageSources>
+</configuration>

src/Markdig.Benchmarks/Markdig.Benchmarks.csproj

@@ -1,6 +1,6 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <OutputType>Exe</OutputType>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <IsPackable>false</IsPackable>
@@ -19,12 +19,12 @@
     </Content>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.13.11" />
-    <PackageReference Include="BenchmarkDotNet.Diagnostics.Windows" Version="0.13.11" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.13.12" />
+    <PackageReference Include="BenchmarkDotNet.Diagnostics.Windows" Version="0.13.12" />
     <PackageReference Include="CommonMark.NET" Version="0.15.1" />
     <PackageReference Include="Markdown" Version="2.2.1" />
     <PackageReference Include="MarkdownSharp" Version="2.0.5" />
-    <PackageReference Include="Microsoft.Diagnostics.Runtime" Version="3.1.456101" />
+    <PackageReference Include="Microsoft.Diagnostics.Runtime" Version="3.1.506101" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Markdig\Markdig.csproj" />

src/Markdig.Tests/Markdig.Tests.csproj

@@ -1,17 +1,17 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net6.0;net8.0</TargetFrameworks>
+    <TargetFramework>net8.0</TargetFramework>
     <OutputType>Exe</OutputType>
     <IsPackable>false</IsPackable>
     <ImplicitUsings>enable</ImplicitUsings>
     <StartupObject>Markdig.Tests.Program</StartupObject>
-    <SpecExecutable>$(MSBuildProjectDirectory)\..\SpecFileGen\bin\$(Configuration)\net6.0\SpecFileGen.dll</SpecExecutable>
-    <SpecTimestamp>$(MSBuildProjectDirectory)\..\SpecFileGen\bin\$(Configuration)\net6.0\SpecFileGen.timestamp</SpecTimestamp>
+    <SpecExecutable>$(MSBuildProjectDirectory)\..\SpecFileGen\bin\$(Configuration)\net8.0\SpecFileGen.dll</SpecExecutable>
+    <SpecTimestamp>$(MSBuildProjectDirectory)\..\SpecFileGen\bin\$(Configuration)\net8.0\SpecFileGen.timestamp</SpecTimestamp>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
     <PackageReference Include="NUnit" Version="4.0.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
   </ItemGroup>

src/Markdig.Tests/TestNormalize.cs

@@ -51,6 +51,16 @@ public class TestNormalize
         });
     }
 
+    [Test]
+    public void SyntaxHeadlineLevel7()
+    {
+        AssertSyntax("####### Headline", new HeadingBlock(null) {
+            HeaderChar = '#',
+            Level = 7,
+            Inline = new ContainerInline().AppendChild(new LiteralInline("Headline")),
+        });
+    }
+
     [Test]
     public void SyntaxParagraph()
     {

src/Markdig.WebApp/Markdig.WebApp.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <PreserveCompilationContext>true</PreserveCompilationContext>
     <AssemblyName>Markdig.WebApp</AssemblyName>
     <ImplicitUsings>enable</ImplicitUsings>

src/Markdig/Extensions/Abbreviations/AbbreviationParser.cs

@@ -20,7 +20,7 @@ public class AbbreviationParser : BlockParser
     /// </summary>
     public AbbreviationParser()
     {
-        OpeningCharacters = new[] { '*' };
+        OpeningCharacters = ['*'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Extensions/AutoIdentifiers/AutoIdentifierExtension.cs

@@ -2,8 +2,6 @@
 // This file is licensed under the BSD-Clause 2 license.
 // See the license.txt file in the project root for more information.
 
-using System.IO;
-
 using Markdig.Helpers;
 using Markdig.Parsers;
 using Markdig.Renderers;

src/Markdig/Extensions/AutoLinks/AutoLinkExtension.cs

@@ -11,14 +11,9 @@ namespace Markdig.Extensions.AutoLinks;
 /// Extension to automatically create <see cref="LinkInline"/> when a link url http: or mailto: is found.
 /// </summary>
 /// <seealso cref="IMarkdownExtension" />
-public class AutoLinkExtension : IMarkdownExtension
+public class AutoLinkExtension(AutoLinkOptions? options) : IMarkdownExtension
 {
-    public readonly AutoLinkOptions Options;
-
-    public AutoLinkExtension(AutoLinkOptions? options)
-    {
-        Options = options ?? new AutoLinkOptions();
-    }
+    public readonly AutoLinkOptions Options = options ?? new AutoLinkOptions();
 
     public void Setup(MarkdownPipelineBuilder pipeline)
     {

src/Markdig/Extensions/AutoLinks/AutoLinkParser.cs

@@ -22,14 +22,14 @@ public class AutoLinkParser : InlineParser
     {
         Options = options ?? throw new ArgumentNullException(nameof(options));
 
-        OpeningCharacters = new char[]
-        {
+        OpeningCharacters =
+        [
             'h', // for http:// and https://
             'f', // for ftp://
             'm', // for mailto:
             't', // for tel:
             'w', // for www.
-        };
+        ];
 
         _listOfCharCache = new ListOfCharCache();
     }

src/Markdig/Extensions/CustomContainers/CustomContainerParser.cs

@@ -17,7 +17,7 @@ public class CustomContainerParser : FencedBlockParserBase<CustomContainer>
     /// </summary>
     public CustomContainerParser()
     {
-        OpeningCharacters = new [] {':'};
+        OpeningCharacters = [':'];
 
         // We don't need a prefix
         InfoPrefix = null;

src/Markdig/Extensions/DefinitionLists/DefinitionListParser.cs

@@ -18,7 +18,7 @@ public class DefinitionListParser : BlockParser
     /// </summary>
     public DefinitionListParser()
     {
-        OpeningCharacters = new [] {':', '~'};
+        OpeningCharacters = [':', '~'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Extensions/Emoji/EmojiMapping.cs

@@ -1786,6 +1786,6 @@ public class EmojiMapping
                 ThrowHelper.ArgumentException(string.Format("Smiley {0} is already present in the emoji mapping", smiley.Key));
         }
 
-        OpeningCharacters = new List<char>(firstChars).ToArray();
+        OpeningCharacters = [.. firstChars];
     }
 }

src/Markdig/Extensions/Figures/FigureBlockParser.cs

@@ -18,7 +18,7 @@ public class FigureBlockParser : BlockParser
     /// </summary>
     public FigureBlockParser()
     {
-        OpeningCharacters = new[] { '^' };
+        OpeningCharacters = ['^'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Extensions/Footers/FooterBlockParser.cs

@@ -19,7 +19,7 @@ public class FooterBlockParser : BlockParser
     /// </summary>
     public FooterBlockParser()
     {
-        OpeningCharacters = new[] {'^'};
+        OpeningCharacters = ['^'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Extensions/Footnotes/FootnoteParser.cs

@@ -22,7 +22,7 @@ public class FootnoteParser : BlockParser
 
     public FootnoteParser()
     {
-        OpeningCharacters = new [] {'['};
+        OpeningCharacters = ['['];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)
@@ -49,7 +49,7 @@ public class FootnoteParser : BlockParser
 
         // Advance the column
         int deltaColumn = processor.Start - start;
-        processor.Column = processor.Column + deltaColumn;
+        processor.Column += deltaColumn;
 
         processor.NextChar(); // Skip ':'
 
@@ -170,10 +170,8 @@ public class FootnoteParser : BlockParser
                 paragraphBlock = new ParagraphBlock();
                 footnote.Add(paragraphBlock);
             }
-            if (paragraphBlock.Inline == null)
-            {
-                paragraphBlock.Inline = new ContainerInline();
-            }
+
+            paragraphBlock.Inline ??= new ContainerInline();
 
             foreach (var link in footnote.Links)
             {

src/Markdig/Extensions/GenericAttributes/GenericAttributesParser.cs

@@ -23,7 +23,7 @@ public class GenericAttributesParser : InlineParser
     /// </summary>
     public GenericAttributesParser()
     {
-        OpeningCharacters = new[] { '{' };
+        OpeningCharacters = ['{'];
     }
 
     public override bool Match(InlineProcessor processor, ref StringSlice slice)
@@ -136,10 +136,7 @@ public class GenericAttributesParser : InlineParser
                 var text = slice.Text.Substring(start, end - start + 1);
                 if (isClass)
                 {
-                    if (classes is null)
-                    {
-                        classes = new List<string>();
-                    }
+                    classes ??= new List<string>();
                     classes.Add(text);
                 }
                 else

src/Markdig/Extensions/Mathematics/MathBlockParser.cs

@@ -20,7 +20,7 @@ public class MathBlockParser : FencedBlockParserBase<MathBlock>
     /// </summary>
     public MathBlockParser()
     {
-        OpeningCharacters = new [] {'$'};
+        OpeningCharacters = ['$'];
         // We expect to match only a $$, no less, no more
         MinimumMatchCount = 2;
         MaximumMatchCount = 2;

src/Markdig/Extensions/Mathematics/MathInlineParser.cs

@@ -21,7 +21,7 @@ public class MathInlineParser : InlineParser
     /// </summary>
     public MathInlineParser()
     {
-        OpeningCharacters = new[] { '$' };
+        OpeningCharacters = ['$'];
         DefaultClass = "math";
     }
 

src/Markdig/Extensions/MediaLinks/HostProviderBuilder.cs

@@ -11,23 +11,19 @@ namespace Markdig.Extensions.MediaLinks;
 
 public class HostProviderBuilder
 {
-    private sealed class DelegateProvider : IHostProvider
+    private sealed class DelegateProvider(
+        string hostPrefix,
+        Func<Uri, string?> handler,
+        bool allowFullscreen = true,
+        string? className = null) : IHostProvider
     {
-        public DelegateProvider(string hostPrefix, Func<Uri, string?> handler, bool allowFullscreen = true, string? className = null)
-        {
-            HostPrefix = hostPrefix;
-            Delegate = handler;
-            AllowFullScreen = allowFullscreen;
-            Class = className;
-        }
+        public string HostPrefix { get; } = hostPrefix;
 
-        public string HostPrefix { get; }
+        public Func<Uri, string?> Delegate { get; } = handler;
 
-        public Func<Uri, string?> Delegate { get; }
+        public bool AllowFullScreen { get; } = allowFullscreen;
 
-        public bool AllowFullScreen { get; }
-
-        public string? Class { get; }
+        public string? Class { get; } = className;
 
         public bool TryHandle(Uri mediaUri, bool isSchemaRelative, [NotNullWhen(true)] out string? iframeUrl)
         {
@@ -71,7 +67,7 @@ public class HostProviderBuilder
 
     #region Known providers
 
-    private static readonly string[] SplitAnd = { "&" };
+    private static readonly string[] SplitAnd = ["&"];
     private static string[] SplitQuery(Uri uri)
     {
         var query = uri.Query.Substring(uri.Query.IndexOf('?') + 1);

src/Markdig/Extensions/NoRefLinks/NoFollowLinksExtension.cs

@@ -17,7 +17,7 @@ public class NoFollowLinksExtension : IMarkdownExtension
 
     public NoFollowLinksExtension()
     {
-        _referralLinksExtension = new ReferralLinksExtension(new[] { "nofollow" });
+        _referralLinksExtension = new ReferralLinksExtension(["nofollow"]);
     }
 
     public void Setup(MarkdownPipelineBuilder pipeline)

src/Markdig/Extensions/SmartyPants/SmartyPantsInlineParser.cs

@@ -19,7 +19,7 @@ public class SmartyPantsInlineParser : InlineParser, IPostInlineProcessor
     /// </summary>
     public SmartyPantsInlineParser()
     {
-        OpeningCharacters = new[] {'\'', '"', '<', '>', '.', '-'};
+        OpeningCharacters = ['\'', '"', '<', '>', '.', '-'];
     }
 
     public override bool Match(InlineProcessor processor, ref StringSlice slice)

src/Markdig/Extensions/Tables/GridTableParser.cs

@@ -12,7 +12,7 @@ public class GridTableParser : BlockParser
 {
     public GridTableParser()
     {
-        OpeningCharacters = new[] { '+' };
+        OpeningCharacters = ['+'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)
@@ -144,7 +144,7 @@ public class GridTableParser : BlockParser
                 line.Start = lineStart + columnSlice.Start + 1;
                 line.End = lineStart + columnSlice.End - 1;
                 line.Trim();
-                if (line.IsEmptyOrWhitespace() || !IsRowSeperator(line))
+                if (line.IsEmptyOrWhitespace() || !IsRowSeparator(line))
                 {
                     hasRowSpan = true;
                     columnSlice.CurrentCell.RowSpan++;
@@ -158,7 +158,7 @@ public class GridTableParser : BlockParser
         }
     }
 
-    private static bool IsRowSeperator(StringSlice slice)
+    private static bool IsRowSeparator(StringSlice slice)
     {
         char c = slice.CurrentChar;
         do
@@ -263,7 +263,7 @@ public class GridTableParser : BlockParser
             }
             sliceForCell.TrimEnd();
 
-            if (!isRowLine || !IsRowSeperator(sliceForCell))
+            if (!isRowLine || !IsRowSeparator(sliceForCell))
             {
                 if (columnSlice.CurrentCell is null)
                 {
@@ -273,10 +273,7 @@ public class GridTableParser : BlockParser
                         ColumnIndex = i
                     };
 
-                    if (columnSlice.BlockProcessor is null)
-                    {
-                        columnSlice.BlockProcessor = processor.CreateChild();
-                    }
+                    columnSlice.BlockProcessor ??= processor.CreateChild();
 
                     // Ensure that the BlockParser is aware that the TableCell is the top-level container
                     columnSlice.BlockProcessor.Open(columnSlice.CurrentCell);

src/Markdig/Extensions/Tables/GridTableState.cs

@@ -10,21 +10,15 @@ namespace Markdig.Extensions.Tables;
 /// <summary>
 /// Internal state used by the <see cref="GridTableParser"/>
 /// </summary>
-internal sealed class GridTableState
+internal sealed class GridTableState(int start, bool expectRow)
 {
-    public GridTableState(int start, bool expectRow)
-    {
-        Start = start;
-        ExpectRow = expectRow;
-    }
-
-    public int Start { get; }
+    public int Start { get; } = start;
 
     public StringLineGroup Lines;
 
     public List<ColumnSlice>? ColumnSlices { get; private set; }
 
-    public bool ExpectRow { get; }
+    public bool ExpectRow { get; } = expectRow;
 
     public int StartRowGroup { get; set; }
 
@@ -45,26 +39,18 @@ internal sealed class GridTableState
         ColumnSlices.Add(new ColumnSlice(start, end, align));
     }
 
-    public sealed class ColumnSlice
+    public sealed class ColumnSlice(int start, int end, TableColumnAlign? align)
     {
-        public ColumnSlice(int start, int end, TableColumnAlign? align)
-        {
-            Start = start;
-            End = end;
-            Align = align;
-            CurrentColumnSpan = -1;
-        }
-
         /// <summary>
         /// Gets or sets the index position of this column (after the |)
         /// </summary>
-        public int Start { get; }
+        public int Start { get; } = start;
 
-        public int End { get; }
+        public int End { get; } = end;
 
-        public TableColumnAlign? Align { get; }
+        public TableColumnAlign? Align { get; } = align;
 
-        public int CurrentColumnSpan { get; set; }
+        public int CurrentColumnSpan { get; set; } = -1;
 
         public int PreviousColumnSpan { get; set; }
 

src/Markdig/Extensions/Tables/PipeTableBlockParser.cs

@@ -22,7 +22,7 @@ public class PipeTableBlockParser : BlockParser
     /// </summary>
     public PipeTableBlockParser()
     {
-        OpeningCharacters = new[] {'-'};
+        OpeningCharacters = ['-'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Extensions/Tables/PipeTableParser.cs

@@ -25,12 +25,12 @@ public class PipeTableParser : InlineParser, IPostInlineProcessor
     /// <summary>
     /// Initializes a new instance of the <see cref="PipeTableParser" /> class.
     /// </summary>
-    /// <param name="lineBreakParser">The linebreak parser to use</param>
+    /// <param name="lineBreakParser">The line break parser to use</param>
     /// <param name="options">The options.</param>
     public PipeTableParser(LineBreakInlineParser lineBreakParser, PipeTableOptions? options = null)
     {
         this.lineBreakParser = lineBreakParser ?? throw new ArgumentNullException(nameof(lineBreakParser));
-        OpeningCharacters = new[] { '|', '\n', '\r' };
+        OpeningCharacters = ['|', '\n', '\r'];
         Options = options ?? new PipeTableOptions();
     }
 
@@ -637,10 +637,10 @@ public class PipeTableParser : InlineParser, IPostInlineProcessor
 
         public int LineIndex { get; set; }
 
-        public List<Inline> ColumnAndLineDelimiters { get; } = new();
+        public List<Inline> ColumnAndLineDelimiters { get; } = [];
 
-        public List<TableCell> Cells { get; } = new();
+        public List<TableCell> Cells { get; } = [];
 
-        public List<Inline> EndOfLines { get; } = new();
+        public List<Inline> EndOfLines { get; } = [];
     }
 }

src/Markdig/Extensions/TaskLists/TaskListInlineParser.cs

@@ -19,7 +19,7 @@ public class TaskListInlineParser : InlineParser
     /// </summary>
     public TaskListInlineParser()
     {
-        OpeningCharacters = new[] {'['};
+        OpeningCharacters = ['['];
         ListClass = "contains-task-list";
         ListItemClass = "task-list-item";
     }

src/Markdig/Extensions/Yaml/YamlFrontMatterParser.cs

@@ -26,7 +26,7 @@ public class YamlFrontMatterParser : BlockParser
     /// </summary>
     public YamlFrontMatterParser()
     {
-        this.OpeningCharacters = new[] { '-' };
+        OpeningCharacters = ['-'];
     }
 
     /// <summary>

src/Markdig/Helpers/BlockWrapper.cs

@@ -7,14 +7,9 @@ using Markdig.Syntax;
 namespace Markdig.Helpers;
 
 // Used to avoid the overhead of type covariance checks
-internal readonly struct BlockWrapper : IEquatable<BlockWrapper>
+internal readonly struct BlockWrapper(Block block) : IEquatable<BlockWrapper>
 {
-    public readonly Block Block;
-
-    public BlockWrapper(Block block)
-    {
-        Block = block;
-    }
+    public readonly Block Block = block;
 
     public static implicit operator Block(BlockWrapper wrapper) => wrapper.Block;
 

src/Markdig/Helpers/CharHelper.cs

@@ -722,11 +722,11 @@ public static class CharHelper
     }
 
     // Used by ListExtraItemParser to format numbers from 1 - 26
-    private static readonly string[] smallNumberStringCache = {
+    private static readonly string[] smallNumberStringCache = [
         "0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
         "10", "11", "12", "13", "14", "15", "16", "17", "18", "19",
         "20", "21", "22", "23", "24", "25", "26",
-    };
+    ];
 
     internal static string SmallNumberToString(int number)
     {

src/Markdig/Helpers/CharacterMap.cs

@@ -35,7 +35,7 @@ public sealed class CharacterMap<T> where T : class
             charSet.Add(map.Key);
         }
 
-        OpeningCharacters = charSet.ToArray();
+        OpeningCharacters = [.. charSet];
         Array.Sort(OpeningCharacters);
 
         _asciiMap = new T[128];

src/Markdig/Helpers/HtmlHelper.cs

@@ -12,8 +12,8 @@ namespace Markdig.Helpers;
 /// </summary>
 public static class HtmlHelper
 {
-    private static readonly char[] SearchBackAndAmp = { '\\', '&' };
-    private static readonly char[] SearchAmp = { '&' };
+    private static readonly char[] SearchBackAndAmp = ['\\', '&'];
+    private static readonly char[] SearchAmp = ['&'];
     private static readonly string[] EscapeUrlsForAscii = new string[128];
 
     static HtmlHelper()

src/Markdig/Helpers/StringLineGroup.cs

@@ -187,16 +187,10 @@ public struct StringLineGroup : IEnumerable
         }
     }
 
-    public struct Enumerator : IEnumerator
+    public struct Enumerator(StringLineGroup parent) : IEnumerator
     {
-        private readonly StringLineGroup _parent;
-        private int _index;
-
-        public Enumerator(StringLineGroup parent)
-        {
-            _parent = parent;
-            _index = -1;
-        }
+        private readonly StringLineGroup _parent = parent;
+        private int _index = -1;
 
         public object Current => _parent.Lines[_index];
 
@@ -452,25 +446,21 @@ public struct StringLineGroup : IEnumerable
         }
     }
 
-    public readonly struct LineOffset
+    public readonly struct LineOffset(
+        int linePosition,
+        int column,
+        int offset,
+        int start,
+        int end)
     {
-        public LineOffset(int linePosition, int column, int offset, int start, int end)
-        {
-            LinePosition = linePosition;
-            Column = column;
-            Offset = offset;
-            Start = start;
-            End = end;
-        }
+        public readonly int LinePosition = linePosition;
 
-        public readonly int LinePosition;
+        public readonly int Column = column;
 
-        public readonly int Column;
+        public readonly int Offset = offset;
 
-        public readonly int Offset;
+        public readonly int Start = start;
 
-        public readonly int Start;
-
-        public readonly int End;
+        public readonly int End = end;
     }
 }

src/Markdig/MarkdownPipeline.cs

@@ -95,18 +95,14 @@ public sealed class MarkdownPipeline
         return new RentedHtmlRenderer(cache, renderer);
     }
 
-    internal sealed class HtmlRendererCache : ObjectCache<HtmlRenderer>
+    internal sealed class HtmlRendererCache(
+        MarkdownPipeline pipeline,
+        bool customWriter = false) : ObjectCache<HtmlRenderer>
     {
-        private static readonly TextWriter s_dummyWriter = new FastStringWriter();
+        private static readonly FastStringWriter s_dummyWriter = new();
 
-        private readonly MarkdownPipeline _pipeline;
-        private readonly bool _customWriter;
-
-        public HtmlRendererCache(MarkdownPipeline pipeline, bool customWriter = false)
-        {
-            _pipeline = pipeline;
-            _customWriter = customWriter;
-        }
+        private readonly MarkdownPipeline _pipeline = pipeline;
+        private readonly bool _customWriter = customWriter;
 
         protected override HtmlRenderer NewInstance()
         {

src/Markdig/MarkdownPipelineBuilder.cs

@@ -24,8 +24,8 @@ public class MarkdownPipelineBuilder
     public MarkdownPipelineBuilder()
     {
         // Add all default parsers
-        BlockParsers = new OrderedList<BlockParser>()
-        {
+        BlockParsers =
+        [
             new ThematicBreakParser(),
             new HeadingBlockParser(),
             new QuoteBlockParser(),
@@ -35,10 +35,10 @@ public class MarkdownPipelineBuilder
             new FencedCodeBlockParser(),
             new IndentedCodeBlockParser(),
             new ParagraphBlockParser(),
-        };
+        ];
 
-        InlineParsers = new OrderedList<InlineParser>()
-        {
+        InlineParsers =
+        [
             new HtmlEntityParser(),
             new LinkInlineParser(),
             new EscapeInlineParser(),
@@ -46,7 +46,7 @@ public class MarkdownPipelineBuilder
             new CodeInlineParser(),
             new AutolinkInlineParser(),
             new LineBreakInlineParser(),
-        };
+        ];
 
         Extensions = new OrderedList<IMarkdownExtension>();
     }

src/Markdig/Parsers/BlockProcessor.cs

@@ -152,7 +152,7 @@ public class BlockProcessor
     /// <summary>
     /// Gets the current stack of <see cref="Block"/> being processed.
     /// </summary>
-    private List<BlockWrapper> OpenedBlocks { get; } = new();
+    private List<BlockWrapper> OpenedBlocks { get; } = [];
 
     private bool ContinueProcessingLine { get; set; }
 

src/Markdig/Parsers/FencedCodeBlockParser.cs

@@ -20,7 +20,7 @@ public class FencedCodeBlockParser : FencedBlockParserBase<FencedCodeBlock>
     /// </summary>
     public FencedCodeBlockParser()
     {
-        OpeningCharacters = new[] {'`', '~'};
+        OpeningCharacters = ['`', '~'];
         InfoPrefix = DefaultInfoPrefix;
     }
 

src/Markdig/Parsers/HeadingBlockParser.cs

@@ -20,7 +20,7 @@ public class HeadingBlockParser : BlockParser, IAttributesParseable
     /// </summary>
     public HeadingBlockParser()
     {
-        OpeningCharacters = new[] {'#'};
+        OpeningCharacters = ['#'];
     }
 
     /// <summary>

src/Markdig/Parsers/HtmlBlockParser.cs

@@ -18,7 +18,7 @@ public class HtmlBlockParser : BlockParser
     /// </summary>
     public HtmlBlockParser()
     {
-        OpeningCharacters = new[] { '<' };
+        OpeningCharacters = ['<'];
     }
        
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Parsers/InlineProcessor.cs

@@ -26,7 +26,7 @@ public delegate void ProcessInlineDelegate(InlineProcessor processor, Inline? in
 /// </summary>
 public class InlineProcessor
 {
-    private readonly List<StringLineGroup.LineOffset> lineOffsets = new();
+    private readonly List<StringLineGroup.LineOffset> lineOffsets = [];
     private int previousSliceOffset;
     private int previousLineIndexForSliceOffset;
 

src/Markdig/Parsers/Inlines/AutolinkInlineParser.cs

@@ -19,7 +19,7 @@ public class AutolinkInlineParser : InlineParser
     /// </summary>
     public AutolinkInlineParser()
     {
-        OpeningCharacters = new[] {'<'};
+        OpeningCharacters = ['<'];
         EnableHtmlParsing = true;
     }
 

src/Markdig/Parsers/Inlines/CodeInlineParser.cs

@@ -21,7 +21,7 @@ public class CodeInlineParser : InlineParser
     /// </summary>
     public CodeInlineParser()
     {
-        OpeningCharacters = new[] { '`' };
+        OpeningCharacters = ['`'];
     }
 
     public override bool Match(InlineProcessor processor, ref StringSlice slice)

src/Markdig/Parsers/Inlines/EmphasisInlineParser.cs

@@ -20,7 +20,7 @@ namespace Markdig.Parsers.Inlines;
 public class EmphasisInlineParser : InlineParser, IPostInlineProcessor
 {
     private CharacterMap<EmphasisDescriptor>? emphasisMap;
-    private readonly DelimitersObjectCache inlinesCache = new DelimitersObjectCache();
+    private readonly DelimitersObjectCache inlinesCache = new();
 
     [Obsolete("Use TryCreateEmphasisInlineDelegate instead", error: false)]
     public delegate EmphasisInline CreateEmphasisInlineDelegate(char emphasisChar, bool isStrong);
@@ -31,11 +31,11 @@ public class EmphasisInlineParser : InlineParser, IPostInlineProcessor
     /// </summary>
     public EmphasisInlineParser()
     {
-        EmphasisDescriptors = new List<EmphasisDescriptor>()
-        {
+        EmphasisDescriptors =
+        [
             new EmphasisDescriptor('*', 1, 2, true),
             new EmphasisDescriptor('_', 1, 2, false)
-        };
+        ];
     }
 
     /// <summary>
@@ -65,7 +65,7 @@ public class EmphasisInlineParser : InlineParser, IPostInlineProcessor
     /// </summary>
     [Obsolete("Use TryCreateEmphasisInlineList instead", error: false)]
     public CreateEmphasisInlineDelegate? CreateEmphasisInline { get; set; }
-    public readonly List<TryCreateEmphasisInlineDelegate> TryCreateEmphasisInlineList = new List<TryCreateEmphasisInlineDelegate>();
+    public readonly List<TryCreateEmphasisInlineDelegate> TryCreateEmphasisInlineList = [];
 
     public override void Initialize()
     {

src/Markdig/Parsers/Inlines/EscapeInlineParser.cs

@@ -15,7 +15,7 @@ public class EscapeInlineParser : InlineParser
 {
     public EscapeInlineParser()
     {
-        OpeningCharacters = new[] {'\\'};
+        OpeningCharacters = ['\\'];
     }
 
     public override bool Match(InlineProcessor processor, ref StringSlice slice)

src/Markdig/Parsers/Inlines/HtmlEntityParser.cs

@@ -21,7 +21,7 @@ public class HtmlEntityParser : InlineParser
     /// </summary>
     public HtmlEntityParser()
     {
-        OpeningCharacters = new[] {'&'};
+        OpeningCharacters = ['&'];
     }
 
     public static bool TryParse(ref StringSlice slice, [NotNullWhen(true)] out string? literal, out int match)

src/Markdig/Parsers/Inlines/LineBreakInlineParser.cs

@@ -18,7 +18,7 @@ public class LineBreakInlineParser : InlineParser
     /// </summary>
     public LineBreakInlineParser()
     {
-        OpeningCharacters = new[] { '\n', '\r' };
+        OpeningCharacters = ['\n', '\r'];
     }
 
     /// <summary>

src/Markdig/Parsers/Inlines/LinkInlineParser.cs

@@ -19,7 +19,7 @@ public class LinkInlineParser : InlineParser
     /// </summary>
     public LinkInlineParser()
     {
-        OpeningCharacters = new[] {'[', ']', '!'};
+        OpeningCharacters = ['[', ']', '!'];
     }
 
     public override bool Match(InlineProcessor processor, ref StringSlice slice)
@@ -322,7 +322,7 @@ public class LinkInlineParser : InlineParser
 
         if (label != null || LinkHelper.TryParseLabelTrivia(ref text, true, out label, out labelSpan))
         {
-            SourceSpan labelWithTrivia = new SourceSpan(labelSpan.Start, labelSpan.End);
+            var labelWithTrivia = new SourceSpan(labelSpan.Start, labelSpan.End);
             if (isLabelSpanLocal)
             {
                 labelSpan = inlineState.GetSourcePositionFromLocalSpan(labelSpan);

src/Markdig/Parsers/MarkdownParser.cs

@@ -210,16 +210,10 @@ public static class MarkdownParser
         }
     }
 
-    private struct ContainerItem
+    private struct ContainerItem(ContainerBlock container)
     {
-        public ContainerItem(ContainerBlock container)
-        {
-            Container = container;
-            Index = 0;
-        }
+        public readonly ContainerBlock Container = container;
 
-        public readonly ContainerBlock Container;
-
-        public int Index;
+        public int Index = 0;
     }
 }

src/Markdig/Parsers/OrderedListItemParser.cs

@@ -15,7 +15,7 @@ public abstract class OrderedListItemParser : ListItemParser
     /// </summary>
     protected OrderedListItemParser()
     {
-        OrderedDelimiters = new[] { '.', ')' };
+        OrderedDelimiters = ['.', ')'];
     }
 
     /// <summary>

src/Markdig/Parsers/QuoteBlockParser.cs

@@ -18,7 +18,7 @@ public class QuoteBlockParser : BlockParser
     /// </summary>
     public QuoteBlockParser()
     {
-        OpeningCharacters = new[] {'>'};
+        OpeningCharacters = ['>'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Parsers/ThematicBreakParser.cs

@@ -16,14 +16,14 @@ public class ThematicBreakParser : BlockParser
     /// <summary>
     /// A singleton instance used by other parsers.
     /// </summary>
-    public static readonly ThematicBreakParser Default = new ThematicBreakParser();
+    public static readonly ThematicBreakParser Default = new();
 
     /// <summary>
     /// Initializes a new instance of the <see cref="ThematicBreakParser"/> class.
     /// </summary>
     public ThematicBreakParser()
     {
-        OpeningCharacters = new[] {'-', '_', '*'};
+        OpeningCharacters = ['-', '_', '*'];
     }
 
     public override BlockState TryOpen(BlockProcessor processor)

src/Markdig/Parsers/UnorderedListItemParser.cs

@@ -15,7 +15,7 @@ public class UnorderedListItemParser : ListItemParser
     /// </summary>
     public UnorderedListItemParser()
     {
-        OpeningCharacters = new [] {'-', '+', '*'};
+        OpeningCharacters = ['-', '+', '*'];
     }
 
     public override bool TryParse(BlockProcessor state, char pendingBulletType, out ListInfo result)

src/Markdig/Polyfills/NullableAttributes.cs

@@ -23,7 +23,7 @@ internal sealed class AllowNullAttribute : Attribute { }
 #if !NET5_0_OR_GREATER
 internal sealed class MemberNotNullAttribute : Attribute
 {
-    public MemberNotNullAttribute(string member) => Members = new[] { member };
+    public MemberNotNullAttribute(string member) => Members = [member];
 
     public MemberNotNullAttribute(params string[] members) => Members = members;
 

src/Markdig/Renderers/Html/HeadingRenderer.cs

@@ -12,14 +12,14 @@ namespace Markdig.Renderers.Html;
 /// <seealso cref="HtmlObjectRenderer{HeadingBlock}" />
 public class HeadingRenderer : HtmlObjectRenderer<HeadingBlock>
 {
-    private static readonly string[] HeadingTexts = {
+    private static readonly string[] HeadingTexts = [
         "h1",
         "h2",
         "h3",
         "h4",
         "h5",
         "h6",
-    };
+    ];
 
     protected override void Write(HtmlRenderer renderer, HeadingBlock obj)
     {

src/Markdig/Renderers/HtmlRenderer.cs

@@ -144,6 +144,8 @@ public class HtmlRenderer : TextRendererBase<HtmlRenderer>
         return this;
     }
 
+    private static readonly SearchValues<char> s_escapedChars = SearchValues.Create("<>&\"");
+
     /// <summary>
     /// Writes the content escaped for HTML.
     /// </summary>
@@ -159,7 +161,7 @@ public class HtmlRenderer : TextRendererBase<HtmlRenderer>
             {
                 int indexOfCharToEscape = softEscape
                     ? content.IndexOfAny('<', '&')
-                    : content.IndexOfAny("<>&\"");
+                    : content.IndexOfAny(s_escapedChars);
 
                 if ((uint)indexOfCharToEscape >= (uint)content.Length)
                 {

src/Markdig/Renderers/Normalize/CodeBlockRenderer.cs

@@ -18,9 +18,9 @@ public class CodeBlockRenderer : NormalizeObjectRenderer<CodeBlock>
     {
         if (obj is FencedCodeBlock fencedCodeBlock)
         {
-            var fencedCharCount = Math.Min(fencedCodeBlock.OpeningFencedCharCount, fencedCodeBlock.ClosingFencedCharCount);
-            var opening = new string(fencedCodeBlock.FencedChar, fencedCharCount);
-            renderer.Write(opening);
+            int fencedCharCount = Math.Min(fencedCodeBlock.OpeningFencedCharCount, fencedCodeBlock.ClosingFencedCharCount);
+
+            renderer.Write(fencedCodeBlock.FencedChar, fencedCharCount);
             if (fencedCodeBlock.Info != null)
             {
                 renderer.Write(fencedCodeBlock.Info);
@@ -41,7 +41,7 @@ public class CodeBlockRenderer : NormalizeObjectRenderer<CodeBlock>
             renderer.WriteLine();
 
             renderer.WriteLeafRawLines(obj, true);
-            renderer.Write(opening);
+            renderer.Write(fencedCodeBlock.FencedChar, fencedCharCount);
         }
         else
         {

src/Markdig/Renderers/Normalize/HeadingRenderer.cs

@@ -12,22 +12,27 @@ namespace Markdig.Renderers.Normalize;
 /// <seealso cref="NormalizeObjectRenderer{HeadingBlock}" />
 public class HeadingRenderer : NormalizeObjectRenderer<HeadingBlock>
 {
-    private static readonly string[] HeadingTexts = {
+    private static readonly string[] HeadingTexts = [
         "#",
         "##",
         "###",
         "####",
         "#####",
         "######",
-    };
+    ];
 
     protected override void Write(NormalizeRenderer renderer, HeadingBlock obj)
-    {
-        var headingText = obj.Level > 0 && obj.Level <= 6
-            ? HeadingTexts[obj.Level - 1]
-            : new string('#', obj.Level);
+    {        
+        if (obj.Level is > 0 and <= 6)
+        {
+            renderer.Write(HeadingTexts[obj.Level - 1]);
+        }
+        else
+        {
+            renderer.Write('#', obj.Level);            
+        }        
 
-        renderer.Write(headingText).Write(' ');
+        renderer.Write(' ');
         renderer.WriteLeafInline(obj);
 
         renderer.FinishBlock(renderer.Options.EmptyLineAfterHeading);

src/Markdig/Renderers/Normalize/Inlines/CodeInlineRenderer.cs

@@ -31,8 +31,8 @@ public class CodeInlineRenderer : NormalizeObjectRenderer<CodeInline>
             if (delimiterCount < count)
                 delimiterCount = count;
         }
-        var delimiterRun = new string(obj.Delimiter, delimiterCount + 1);
-        renderer.Write(delimiterRun);
+
+        renderer.Write(obj.Delimiter, delimiterCount + 1);
         if (content.Length != 0)
         {
             if (content[0] == obj.Delimiter)
@@ -49,6 +49,6 @@ public class CodeInlineRenderer : NormalizeObjectRenderer<CodeInline>
         {
             renderer.Write(' ');
         }
-        renderer.Write(delimiterRun);
+        renderer.Write(obj.Delimiter, delimiterCount + 1);
     }
 }

src/Markdig/Renderers/Normalize/Inlines/EmphasisInlineRenderer.cs

@@ -14,9 +14,8 @@ public class EmphasisInlineRenderer : NormalizeObjectRenderer<EmphasisInline>
 {
     protected override void Write(NormalizeRenderer renderer, EmphasisInline obj)
     {
-        var emphasisText = new string(obj.DelimiterChar, obj.DelimiterCount);
-        renderer.Write(emphasisText);
+        renderer.Write(obj.DelimiterChar, obj.DelimiterCount);
         renderer.WriteChildren(obj);
-        renderer.Write(emphasisText);
+        renderer.Write(obj.DelimiterChar, obj.DelimiterCount);
     }
 }

src/Markdig/Renderers/Roundtrip/CodeBlockRenderer.cs

@@ -19,8 +19,7 @@ public class CodeBlockRenderer : RoundtripObjectRenderer<CodeBlock>
         if (obj is FencedCodeBlock fencedCodeBlock)
         {
             renderer.Write(obj.TriviaBefore);
-            var opening = new string(fencedCodeBlock.FencedChar, fencedCodeBlock.OpeningFencedCharCount);
-            renderer.Write(opening);
+            renderer.Write(fencedCodeBlock.FencedChar, fencedCodeBlock.OpeningFencedCharCount);
 
             if (!fencedCodeBlock.TriviaAfterFencedChar.IsEmpty)
             {
@@ -56,9 +55,8 @@ public class CodeBlockRenderer : RoundtripObjectRenderer<CodeBlock>
             renderer.WriteLeafRawLines(obj);
 
             renderer.Write(fencedCodeBlock.TriviaBeforeClosingFence);
-            var closing = new string(fencedCodeBlock.FencedChar, fencedCodeBlock.ClosingFencedCharCount);
-            renderer.Write(closing);
-            if (!string.IsNullOrEmpty(closing))
+            renderer.Write(fencedCodeBlock.FencedChar, fencedCodeBlock.ClosingFencedCharCount);
+            if (fencedCodeBlock.ClosingFencedCharCount > 0)
             {
                 // See example 207: "> ```\nfoo\n```"
                 renderer.WriteLine(obj.NewLine);

src/Markdig/Renderers/Roundtrip/HeadingRenderer.cs

@@ -12,14 +12,14 @@ namespace Markdig.Renderers.Roundtrip;
 /// <seealso cref="RoundtripObjectRenderer{HeadingBlock}" />
 public class HeadingRenderer : RoundtripObjectRenderer<HeadingBlock>
 {
-    private static readonly string[] HeadingTexts = {
+    private static readonly string[] HeadingTexts = [
         "#",
         "##",
         "###",
         "####",
         "#####",
         "######",
-    };
+    ];
 
     protected override void Write(RoundtripRenderer renderer, HeadingBlock obj)
     {
@@ -28,12 +28,11 @@ public class HeadingRenderer : RoundtripObjectRenderer<HeadingBlock>
             renderer.RenderLinesBefore(obj);
 
             var headingChar = obj.Level == 1 ? '=' : '-';
-            var line = new string(headingChar, obj.HeaderCharCount);
 
             renderer.WriteLeafInline(obj);
             renderer.WriteLine(obj.SetextNewline);
             renderer.Write(obj.TriviaBefore);
-            renderer.Write(line);
+            renderer.Write(headingChar, obj.HeaderCharCount);
             renderer.WriteLine(obj.NewLine);
             renderer.Write(obj.TriviaAfter);
 
@@ -43,12 +42,17 @@ public class HeadingRenderer : RoundtripObjectRenderer<HeadingBlock>
         {
             renderer.RenderLinesBefore(obj);
 
-            var headingText = obj.Level > 0 && obj.Level <= 6
-                ? HeadingTexts[obj.Level - 1]
-                : new string('#', obj.Level);
-
             renderer.Write(obj.TriviaBefore);
-            renderer.Write(headingText);
+
+            if (obj.Level is > 0 and <= 6)
+            {
+                renderer.Write(HeadingTexts[obj.Level - 1]);
+            }
+            else
+            {
+                renderer.Write('#', obj.Level);
+            }
+
             renderer.Write(obj.TriviaAfterAtxHeaderChar);
             renderer.WriteLeafInline(obj);
             renderer.Write(obj.TriviaAfter);

src/Markdig/Renderers/Roundtrip/Inlines/CodeInlineRenderer.cs

@@ -14,12 +14,11 @@ public class CodeInlineRenderer : RoundtripObjectRenderer<CodeInline>
 {
     protected override void Write(RoundtripRenderer renderer, CodeInline obj)
     {
-        var delimiterRun = new string(obj.Delimiter, obj.DelimiterCount);
-        renderer.Write(delimiterRun);
+        renderer.Write(obj.Delimiter, obj.DelimiterCount);
         if (!obj.ContentSpan.IsEmpty)
         {
             renderer.Write(obj.ContentWithTrivia);
         }
-        renderer.Write(delimiterRun);
+        renderer.Write(obj.Delimiter, obj.DelimiterCount);
     }
 }

src/Markdig/Renderers/Roundtrip/Inlines/EmphasisInlineRenderer.cs

@@ -14,9 +14,8 @@ public class EmphasisInlineRenderer : RoundtripObjectRenderer<EmphasisInline>
 {
     protected override void Write(RoundtripRenderer renderer, EmphasisInline obj)
     {
-        var emphasisText = new string(obj.DelimiterChar, obj.DelimiterCount);
-        renderer.Write(emphasisText);
+        renderer.Write(obj.DelimiterChar, obj.DelimiterCount);
         renderer.WriteChildren(obj);
-        renderer.Write(emphasisText);
+        renderer.Write(obj.DelimiterChar, obj.DelimiterCount);
     }
 }

src/Markdig/Renderers/TextRendererBase.cs

@@ -211,6 +211,25 @@ public abstract class TextRendererBase<T> : TextRendererBase where T : TextRende
         return (T)this;
     }
 
+    /// <summary>
+    /// Writes the specified char repeated a specified number of times.
+    /// </summary>
+    /// <param name="c">The char to write.</param>
+    /// <param name="count">The number of times to write the char.</param>
+    /// <returns>This instance</returns>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    internal T Write(char c, int count)
+    {
+        WriteIndent();        
+        
+        for (int i = 0; i < count; i++)
+        {
+            Writer.Write(c);
+        }        
+
+        return (T)this;
+    }
+
     /// <summary>
     /// Writes the specified slice.
     /// </summary>

src/Markdig/Syntax/CodeBlock.cs

@@ -21,7 +21,7 @@ public class CodeBlock : LeafBlock
     }
 
     private List<CodeBlockLine>? _codeBlockLines;
-    public List<CodeBlockLine> CodeBlockLines => _codeBlockLines ??= new();
+    public List<CodeBlockLine> CodeBlockLines => _codeBlockLines ??= [];
 
     /// <summary>
     /// Initializes a new instance of the <see cref="CodeBlock"/> class.

src/Markdig/Syntax/ContainerBlock.cs

@@ -27,7 +27,7 @@ public abstract class ContainerBlock : Block, IList<Block>, IReadOnlyList<Block>
     /// <param name="parser">The parser used to create this block.</param>
     protected ContainerBlock(BlockParser? parser) : base(parser)
     {
-        _children = Array.Empty<BlockWrapper>();
+        _children = [];
         SetTypeKind(isInline: false, isContainer: true);
     }
 
@@ -301,14 +301,9 @@ public abstract class ContainerBlock : Block, IList<Block>, IReadOnlyList<Block>
 
     #endregion
 
-    private sealed class BlockComparisonWrapper : IComparer<BlockWrapper>
+    private sealed class BlockComparisonWrapper(Comparison<Block> comparison) : IComparer<BlockWrapper>
     {
-        private readonly Comparison<Block> _comparison;
-
-        public BlockComparisonWrapper(Comparison<Block> comparison)
-        {
-            _comparison = comparison;
-        }
+        private readonly Comparison<Block> _comparison = comparison;
 
         public int Compare(BlockWrapper x, BlockWrapper y)
         {
@@ -316,14 +311,9 @@ public abstract class ContainerBlock : Block, IList<Block>, IReadOnlyList<Block>
         }
     }
 
-    private sealed class BlockComparerWrapper : IComparer<BlockWrapper>
+    private sealed class BlockComparerWrapper(IComparer<Block> comparer) : IComparer<BlockWrapper>
     {
-        private readonly IComparer<Block> _comparer;
-
-        public BlockComparerWrapper(IComparer<Block> comparer)
-        {
-            _comparer = comparer;
-        }
+        private readonly IComparer<Block> _comparer = comparer;
 
         public int Compare(BlockWrapper x, BlockWrapper y)
         {

src/Markdig/Syntax/MarkdownObject.cs

@@ -155,16 +155,10 @@ public abstract class MarkdownObject : IMarkdownObject
 
     private class DataEntriesAndTrivia
     {
-        private struct DataEntry
+        private struct DataEntry(object key, object value)
         {
-            public readonly object Key;
-            public object Value;
-
-            public DataEntry(object key, object value)
-            {
-                Key = key;
-                Value = value;
-            }
+            public readonly object Key = key;
+            public object Value = value;
         }
 
         private DataEntry[]? _entries;

src/Markdig/Syntax/QuoteBlock.cs

@@ -42,7 +42,7 @@ public class QuoteBlock : ContainerBlock
 public class QuoteBlockLine
 {
     /// <summary>
-    /// Gets or sets trivia occuring before the first quote character.
+    /// Gets or sets trivia occurring before the first quote character.
     /// </summary>
     public StringSlice TriviaBefore { get; set; }
 

src/Markdig/Syntax/SourceSpan.cs

@@ -37,26 +37,26 @@ public struct SourceSpan : IEquatable<SourceSpan>
     /// <summary>
     /// Gets the character length of this element within the original source code.
     /// </summary>
-    public int Length => End - Start + 1;
+    public readonly int Length => End - Start + 1;
 
-    public bool IsEmpty => Start > End;
+    public readonly bool IsEmpty => Start > End;
 
     public SourceSpan MoveForward(int count)
     {
         return new SourceSpan(Start + count, End + count);
     }
 
-    public bool Equals(SourceSpan other)
+    public readonly bool Equals(SourceSpan other)
     {
         return Start == other.Start && End == other.End;
     }
 
-    public override bool Equals(object? obj)
+    public override readonly bool Equals(object? obj)
     {
         return obj is SourceSpan sourceSpan && Equals(sourceSpan);
     }
 
-    public override int GetHashCode()
+    public override readonly int GetHashCode()
     {
         unchecked
         {
@@ -74,7 +74,7 @@ public struct SourceSpan : IEquatable<SourceSpan>
         return !left.Equals(right);
     }
 
-    public override string ToString()
+    public override readonly string ToString()
     {
         return $"{Start}-{End}";
     }

src/SpecFileGen/SpecFileGen.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <IsPackable>false</IsPackable>
   </PropertyGroup>

src/UnicodeNormDApp/UnicodeNormDApp.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>

src/mdtoc/mdtoc.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>