https://github.com/crwsolutions/ntokenizers

Collection of stream-capable tokenizers for JSON, YAML, XML, SQL, Typescript, CSS, CSharp and Markup processing
https://github.com/crwsolutions/ntokenizers

csharp-parser css-parser dotnet javascript-parser json-parser markup-parser sql-parser stream streaming tokenizer typescript-parser xml-parser

Last synced: 2 days ago
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Collection of stream-capable tokenizers for JSON, YAML, XML, SQL, Typescript, CSS, CSharp and Markup processing

• Host: GitHub
• URL: https://github.com/crwsolutions/ntokenizers
• Owner: crwsolutions
• License: mit
• Created: 2025-11-15T12:13:25.000Z (7 months ago)
• Default Branch: main
• Last Pushed: 2026-05-26T15:04:28.000Z (6 days ago)
• Last Synced: 2026-05-26T16:36:36.744Z (6 days ago)
• Topics: csharp-parser, css-parser, dotnet, javascript-parser, json-parser, markup-parser, sql-parser, stream, streaming, tokenizer, typescript-parser, xml-parser
• Language: C#
• Homepage: https://crwsolutions.github.io/ntokenizers
• Size: 572 KB
• Stars: 0
• Watchers: 0
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE

Awesome Lists containing this project

README

          
# NTokenizers

Lightweight **Stream Tokenizers** for syntax highlighting and formatting. Perfect building block for **chat applications**, and **AI response rendering** . Tokenize streaming AI responses in real-time for beautiful syntax-highlighted output.

| Markup languages | Data formats | Programming languages |

|------------------|--------------|----------------------|

| Markdown | JSON | CSharp |

| HTML | YAML | C |

| | TOML | C++ |

| | XML | Go |

| | | Java |

| | | Kotlin |

| | | Rust |

| | | Swift |

| | | TypeScript |

| | | SQL |

| | | CSS |

| | | Python |

## How to: kickoff token processing

### Composite tokenizers

#### Markup languages

```csharp

// kickoff markdown tokenizer

await MarkdownTokenizer.Create().ParseAsync(stream, onToken: async token => { /* handle markdown-tokens here */ });

// kickoff html tokenizer

await HtmlTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle html-tokens here */ });

```

### Individual tokenizers

#### Data formats

```csharp

// kickoff json tokenizer

await JsonTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle json-tokens here */ });

// kickoff yaml tokenizer

await YamlTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle yaml-tokens here */ });

// kickoff toml tokenizer

await TomlTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle toml-tokens here */ });

// kickoff xml tokenizer

await XmlTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle xml-tokens here */ });

```

#### Programming languages

```csharp

// kickoff csharp tokenizer

await CSharpTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle csharp-tokens here */ });

// kickoff c tokenizer

await CTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle c-tokens here */ });

// kickoff cpp tokenizer

await CppTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle cpp-tokens here */ });

// kickoff go tokenizer

await GoTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle go-tokens here */ });

// kickoff java tokenizer

await JavaTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle java-tokens here */ });

// kickoff kotlin tokenizer

await KotlinTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle kotlin-tokens here */ });

// kickoff rust tokenizer

await RustTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle rust-tokens here */ });

// kickoff swift tokenizer

await SwiftTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle swift-tokens here */ });

// kickoff typescript/ javascript tokenizer

await TypescriptTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle typescript-tokens here */ });

// kickoff sql tokenizer

await SqlTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle sql-tokens here */ });

// kickoff css tokenizer

await CssTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle css-tokens here */ });

// kickoff python tokenizer

await PythonTokenizer.Create().ParseAsync(stream, onToken: token => { /* handle python-tokens here */ });

```

## Overview

NTokenizers is a .NET library written in C# that provides tokenizers for processing structured text formats like Markdown, JSON, XML, HTML, YAML, TOML, SQL, Typescript, CSS, CSharp, C, C++, Go, Java, Kotlin, Rust, Swift and Python. The `Tokenize` method is the core functionality that breaks down structured text into meaningful components (tokens) for processing. Its key feature is **stream processing capability** - it can handle data as it arrives in real-time, making it ideal for processing large files or streaming data without loading everything into memory at once.

> [!WARNING] 

>

> These tokenizers are **not validation-based** and are primarily intended for **prettifying**, **formatting**, or **visualizing** structured text. They do not perform strict validation of the input format, so they may produce unexpected results when processing malformed or invalid XML, JSON, or HTML. Use them with caution when dealing with untrusted or poorly formatted input.

> [!WARNING] 

>

> MarkupTokenizer was renamed to MarkdownTokenizer in v2.

## Used by

- [NTokenizers.Extensions.Spectre.Console](https://www.nuget.org/packages/NTokenizers.Extensions.Spectre.Console/) Spectre.Console rendering extensions for NTokenizers, Style-rich console syntax highlighting.

# Architecture

Most **tokenizers**, such as json, xml, or etc..., can be used individually, depending on the specific format you want to parse.

The `MarkdownTokenizer` however is a special case. Instead of working on a single format, it acts as a **composite tokenizer**, using the other tokenizers as **subtokenizers**. When parsing a stream, MarkdownTokenizer delegates portions of the input to the appropriate subtokenizer, allowing it to handle multiple formats seamlessly in one pass.

The same principle applies to inline tokenizers such as Heading, Blockquote, ListItem, and others. However, they cannot be used individually and produce the same token types as the `MarkdownTokenizer`.

### Diagram

```

         ┌─────────┐

         │ stream  │

         └─────────┘

              │  ParseAsync()

              ▼

   ┌─────────────────────┐

   │  MarkdownTokenizer  │ ───────────► fire markdown tokens

   └─────────────────────┘

              │

              ▼       ┌─────────┐

              ├──────►│   json  │ ───► fire json tokens

              │       └─────────┘

              │

              │       ┌─────────┐

              ├──────►│ Heading │ ───► fire markdown tokens

              │       └─────────┘

              │

              │       ┌─────────┐

              ├──────►│   html  │ ───► fire html tokens

              │       └─────────┘

              │            │

              │            ▼       ┌─────────┐

              │            ├──────►│   css   │ ───► fire css tokens

              │            │       └─────────┘

              │            │

              │            │       ┌─────────┐

              │            └──────►│ script  │ ───► fire typescript tokens

              │                    └─────────┘

              │       ┌─────────┐

              └──────►│  etc..  │ ───► etc

                      └─────────┘

```

## Example

Here's a simple example showing how to use the `MarkdownTokenizer`:

```csharp

using NTokenizers.Core;

using NTokenizers.Css;

using NTokenizers.Html;

using NTokenizers.Json;

using NTokenizers.Markdown;

using NTokenizers.Markdown.Metadata;

using NTokenizers.Typescript;

using NTokenizers.Xml;

using Spectre.Console;

using System.Diagnostics;

using System.IO.Pipes;

using System.Text;

class Program

{

    static async Task Main()

    {

        string markdown = """

        Here is some **bold** text and some *italic* text.

        # NTokenizers Showcase

        

        ## Css example

        ```css

        .user {

            color: #FFFFFF;

            active: true;

        }

        ```

        ## XML example

        ```xml

        

            Laura Smith

        

        ```

        ## HTML example

        ```html

        

        

            

                body { font-family: Arial, sans-serif; background-color: #f0f8ff; }

                .header { color: #4682b4; text-align: center; }

                .content { margin: 20px; padding: 15px; background-color: white; border-radius: 5px; }

            

        

        

            
Hello world!

            

                console.log("Hello from the sample script!");

                document.addEventListener('DOMContentLoaded', function() {

                    console.log("DOM is fully loaded");

                });

            

        

        

        ```


        ## JSON example

        ```json

        {

            "name": "Laura Smith",

            "active": true

        }

        ```

        ## TypeScript example

        ```typescript

        const user = {

            name: "Laura Smith",

            active: true

        };

        ```

        """;

        // Create connected streams

        using var pipe = new AnonymousPipeServerStream(PipeDirection.Out);

        using var reader = new AnonymousPipeClientStream(PipeDirection.In, pipe.ClientSafePipeHandle);

        // Start slow writer

        var writerTask = EmitSlowlyAsync(markdown, pipe);

        // Parse markup

        await MarkdownTokenizer.Create().ParseAsync(reader, onToken: async token =>

        {

            if (token.Metadata is ICodeBlockMetadata codeBlock)

            {

                AnsiConsole.WriteLine();

                AnsiConsole.Write(new Markup($"[bold lime]{codeBlock.Language}:[/]"));

                AnsiConsole.WriteLine();

            }

            if (token.Metadata is ListItemMetadata listMetadata)

            {

                AnsiConsole.Write(new Markup($"[bold lime]{listMetadata.Marker} [/]"));

                await listMetadata.RegisterInlineTokenHandler(inlineToken =>

                {

                    var value = Markup.Escape(inlineToken.Value);

                    AnsiConsole.Write(new Markup($"[bold red]{value}[/]"));

                });

                Debug.WriteLine("Written listItem inlines");

            }

            else if (token.Metadata is HeadingMetadata headingMetadata)

            {

                await headingMetadata.RegisterInlineTokenHandler(inlineToken =>

                {

                    var value = Markup.Escape(inlineToken.Value);

                    var colored = headingMetadata.Level != 1 ?

                        new Markup($"[bold GreenYellow]{value}[/]") :

                        new Markup($"[bold yellow]** {value} **[/]");

                    AnsiConsole.Write(colored);

                });

                Debug.WriteLine("Written Heading inlines");

            }

            else if (token.Metadata is XmlCodeBlockMetadata xmlMetadata)

            {

                await xmlMetadata.RegisterInlineTokenHandler(inlineToken =>

                {

                    var value = Markup.Escape(inlineToken.Value);

                    var colored = inlineToken.TokenType switch

                    {

                        XmlTokenType.ElementName => new Markup($"[blue]{value}[/]"),

                        XmlTokenType.OpeningAngleBracket => new Markup($"[yellow]{value}[/]"),

                        XmlTokenType.ClosingAngleBracket => new Markup($"[yellow]{value}[/]"),

                        XmlTokenType.SelfClosingSlash => new Markup($"[yellow]{value}[/]"),

                        XmlTokenType.AttributeName => new Markup($"[cyan]{value}[/]"),

                        XmlTokenType.AttributeEquals => new Markup($"[yellow]{value}[/]"),

                        XmlTokenType.AttributeQuote => new Markup($"[grey]{value}[/]"),

                        XmlTokenType.AttributeValue => new Markup($"[green]{value}[/]"),

                        XmlTokenType.Text => new Markup($"[white]{value}[/]"),

                        XmlTokenType.Whitespace => new Markup($"[grey]{value}[/]"),

                        _ => new Markup(value)

                    };

                    AnsiConsole.Write(colored);

                });

            }

            else if (token.Metadata is JsonCodeBlockMetadata jsonMetadata)

            {

                await jsonMetadata.RegisterInlineTokenHandler(inlineToken =>

                {

                    var value = Markup.Escape(inlineToken.Value);

                    var colored = inlineToken.TokenType switch

                    {

                        JsonTokenType.StartObject => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.EndObject => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.StartArray => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.EndArray => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.PropertyName => new Markup($"[cyan]{value}[/]"),

                        JsonTokenType.StringValue => new Markup($"[green]{value}[/]"),

                        JsonTokenType.Number => new Markup($"[magenta]{value}[/]"),

                        JsonTokenType.True => new Markup($"[orange1]{value}[/]"),

                        JsonTokenType.False => new Markup($"[orange1]{value}[/]"),

                        JsonTokenType.Null => new Markup($"[grey]{value}[/]"),

                        JsonTokenType.Colon => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.Comma => new Markup($"[yellow]{value}[/]"),

                        JsonTokenType.Whitespace => new Markup($"[grey]{value}[/]"),

                        _ => new Markup(value)

                    };

                    AnsiConsole.Write(colored);

                });

            }

            else if (token.Metadata is HtmlCodeBlockMetadata htmlMetadata)

            {

                await htmlMetadata.RegisterInlineTokenHandler(async inlineToken =>

                {

                    if (inlineToken.Metadata is TypeScriptCodeBlockMetadata tsMeta)

                    {

                        await HandleScript(tsMeta);

                    }

                    else if (inlineToken.Metadata is CssCodeBlockMetadata cssMeta)

                    {

                        await HandleCss(cssMeta);

                    }

                    else

                    {

                    var value = Markup.Escape(inlineToken.Value);

                    var colored = inlineToken.TokenType switch

                    {

                        HtmlTokenType.OpeningAngleBracket => new Markup($"[yellow]{value}[/]"),

                        HtmlTokenType.ClosingAngleBracket => new Markup($"[yellow]{value}[/]"),

                        HtmlTokenType.SelfClosingSlash => new Markup($"[yellow]{value}[/]"),

                        HtmlTokenType.AttributeName => new Markup($"[cyan]{value}[/]"),

                        HtmlTokenType.AttributeEquals => new Markup($"[yellow]{value}[/]"),

                        HtmlTokenType.AttributeQuote => new Markup($"[grey]{value}[/]"),

                        HtmlTokenType.AttributeValue => new Markup($"[green]{value}[/]"),

                        HtmlTokenType.Text => new Markup($"[white]{value}[/]"),

                        HtmlTokenType.Comment => new Markup($"[grey]{value}[/]"),

                        HtmlTokenType.Whitespace => new Markup($"[grey]{value}[/]"),

                        _ => new Markup(value)

                    };

                    AnsiConsole.Write(colored);

                    }

                });

            }

            else if (token.Metadata is TypeScriptCodeBlockMetadata tsMetadata)

            {

                await HandleScript(tsMetadata);

            }

            else if (token.Metadata is CssCodeBlockMetadata cssMetadata)

            {

                await HandleCss(cssMetadata);

            }

            else

            {

                // Handle regular markup tokens

                var value = Markup.Escape(token.Value);

                var colored = token.TokenType switch

                {

                    MarkdownTokenType.Text => new Markup($"{value}"),

                    MarkdownTokenType.Bold => new Markup($"[bold]{value}[/]"),

                    MarkdownTokenType.Italic => new Markup($"[italic]{value}[/]"),

                    _ => new Markup(value)

                };

                AnsiConsole.Write(colored);

            }

            if (token.Metadata is InlineMetadata)

            {

                AnsiConsole.WriteLine();

            }

        });

        await writerTask;

        Console.WriteLine();

        Console.WriteLine("Done.");

    }

    private static async Task HandleScript(TypeScriptCodeBlockMetadata tsMetadata)

    {

        await tsMetadata.RegisterInlineTokenHandler(inlineToken =>

        {

            var value = Markup.Escape(inlineToken.Value);

            var colored = inlineToken.TokenType switch

            {

                TypescriptTokenType.Identifier => new Markup($"[cyan]{value}[/]"),

                TypescriptTokenType.Keyword => new Markup($"[blue]{value}[/]"),

                TypescriptTokenType.StringValue => new Markup($"[green]{value}[/]"),

                TypescriptTokenType.Number => new Markup($"[magenta]{value}[/]"),

                TypescriptTokenType.Operator => new Markup($"[yellow]{value}[/]"),

                TypescriptTokenType.Comment => new Markup($"[grey]{value}[/]"),

                TypescriptTokenType.Whitespace => new Markup($"[grey]{value}[/]"),

                _ => new Markup(value)

            };

            AnsiConsole.Write(colored);

        });

    }

    private static async Task HandleCss(CssCodeBlockMetadata cssMetadata)

    {

        await cssMetadata.RegisterInlineTokenHandler(inlineToken =>

        {

            var value = Markup.Escape(inlineToken.Value);

            var colored = inlineToken.TokenType switch

            {

                CssTokenType.Identifier => new Markup($"[white]{value}[/]"),

                CssTokenType.Number => new Markup($"[magenta]{value}[/]"),

                CssTokenType.Operator => new Markup($"[yellow]{value}[/]"),

                CssTokenType.Selector => new Markup($"[yellow]{value}[/]"),

                CssTokenType.Comment => new Markup($"[green]{value}[/]"),

                CssTokenType.Whitespace => new Markup($"[grey]{value}[/]"),

                _ => new Markup(value)

            };

            AnsiConsole.Write(colored);

        });

    }

    static async Task EmitSlowlyAsync(string markdown, Stream output)

    {

        var rng = new Random();

        byte[] bytes = Encoding.UTF8.GetBytes(markdown);

        foreach (var b in bytes)

        {

            await output.WriteAsync(new[] { b }.AsMemory(0, 1));

            await output.FlushAsync();

            await Task.Delay(rng.Next(0, 2));

        }

        output.Close(); // EOF

    }

}

```

For more information, check out the documentation [here](https://crwsolutions.github.io/ntokenizers/).