Nest.Text

Nest.Text is a zero-dependency, fluent structured text generation library that helps you build structured content with ease — from C#, Python, and YAML to HTML, XML, and more. It lets you describe what to generate — Nest takes care of how it's formatted.

🔗 Links

• 📦 NuGet: Nest.Text on NuGet
• 💻 GitHub: github.com/h-shahzaib/Nest.Text

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Quick Navigation

• Installation
• Core API
• Line Break Behavior
• Configuration Options
• Character Replacement
• Reusing Builder Patterns
• Examples
• Debugging

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Installation

dotnet add package Nest.Text

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What Is It?

Nest.Text provides a builder-style API to generate code, markup, or any structured text using:

• .L(...) – Write one or more lines
• .B(b => { }) – Begin a block with nested content
• .L(...).B(b => { }) – Write a logical group of content

Nest adds or avoids line breaks based on chaining and structure awareness.

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Line Break Behavior

Understanding how line breaks work with different usage patterns:

Usage Patterns

Lines

_.L("one");
_.L("two");
_.L("one");
_.L("two");

• ❌ No line break will be added between these lines

Multiple Lines

✅ Line break will be added here
_.L(
    "one",
    "two"
);
✅ Line break will be added here
_.L("one");
_.L("two");

Multi-Line raw string literal

✅ Line break will be added here
_.L(
    """
    one
    two
    """
);
✅ Line break will be added here
_.L(
    """
    one
    two
    """
);
✅ Line break will be added here

Strings having line breaks

✅ Line break will be added here
_.L("one \n two");
_.L(); ⚠️ First explicit line break will override implicit line break
_.L(); ✅ Explicit line break will be added here
_.L("one \n two");
✅ Line break will be added here

Method Chaining

✅ Line break will be added here
_.L("one")
 .L("two").B(_ => 
 {
    _.L("three");
 });
✅ Line break will be added here

• ❌ No line break between chained calls

---

Options

_.Options.BlockStyle = BlockStyle.CurlyBraces;     // Choose between 'CurlyBraces' or 'IndentOnly' (default)
_.Options.IndentChar = ' ';                        // Character used for indentation (e.g., space or tab)
_.Options.IndentSize = 4;                          // Number of indent characters per level

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Live Behavior & Inheritance

Options in Nest.Text are live — changes apply immediately and affect all content added after the change.

Live Indent Example

_.L("Console.WriteLine(`A`)"); // uses current indent size (e.g. 4)

_.Options.IndentSize = 0;
_.L("Console.WriteLine(`B`)"); // will have no indentation

_.Options.IndentSize = 4;
_.L("Console.WriteLine(`C`)"); // will again be indented

Each line reflects the indent size active at the time it's written.

---

Character Replacement

You can register characters to be replaced with other characters:

_.Options.RegisterCharReplacement('`', '"');

And then use backticks (`) instead of escaped quotes in your strings:

_.L("Console.WriteLine(`Hello World!`);"); 
// Outputs: Console.WriteLine("Hello World!");

---

BlockStyle

Changing the BlockStyle will, by default, apply the new style to all blocks, including nested ones.

_.L("namespace Demo").B(_ =>
{
    _.L("class A").B(_ =>
    {
        _.L("void Print()").B(_ =>
        {
            _.L("print(`Hello`)");
        });
    });

     _.Options.BlockStyle = BlockStyle.CurlyBraces;

    _.L("class A").B(_ =>
    {
        _.L("void Print()").B(_ =>
        {
            _.L("print(`Hello`)");
        });
    });
});

✅ all blocks after the change inside namespace Demo will use CurlyBraces.

---

Reusing Common Builder Patterns

Since .B() accepts a lambda, you can pass a method that takes an ITextBuilder parameter — this lets you keep the structure clean by moving code blocks into reusable methods.

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✅ Example: Extracting an If-Else Block

Instead of writing everything inline:

_.L("if (count > 6)").B(_ =>
{
    _.L("Console.WriteLine(`Hello World!`);");
    _.L("Console.WriteLine(`Hello Again!`);");
})
.L("else").B(_ =>
{
    _.L("Console.WriteLine(`Hello World!`);");
});

You can extract it into a separate method:

void AddIfElse(ITextBuilder _)
{
    _.L("if (count > 6)").B(_ =>
    {
        _.L("Console.WriteLine(`Hello World!`);");
        _.L("Console.WriteLine(`Hello Again!`);");
    })
    .L("else").B(_ =>
    {
        _.L("Console.WriteLine(`Hello World!`);");
    });
}

And call it like this:

_.L("public static void Main(string[] args)").B(_ => AddIfElse(_));

✅ This keeps the Main method block clean and readable.

---

Using .Append()

.Append() allows you to insert multiple external methods cleanly:

_.L("public static void Main(string[] args)").B(_ => 
    _.Append(_ => AddIfElse(_)).Append(_ => AddLoop(_))
);

Each method AddIfElse(), AddLoop() still receives the same builder instance, so indentation and formatting stay consistent.

---

Using .Chain()

If you're inside a chain, use .Chain() and pass a method that takes IChainBuilder:

void AddMainBody(IChainBuilder _)
{
    _.B(_ =>
    {
        _.L("if (count > 6)").B(_ =>
        {
            _.L("Console.WriteLine(`Hello World!`);");
        })
        .L("else").B(_ =>
        {
            _.L("Console.WriteLine(`Goodbye!`);");
        });
    });
}

Then call it like:

_.L("public static void Main(string[] args)")
    .Chain(_ => AddMainBody(_));

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Why?

• ✅ Keeps your generation logic modular.
• ✅ Makes complex structures easier to read and maintain.
• ✅ Allows mixing and matching reusable blocks.

This approach is especially helpful when generating large sections like methods, conditionals, loops, or class structures.

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Examples

Below are a few examples of how you can generate code for different languages:

#️⃣ C# Example (CurlyBraces)

var _ = TextBuilder.Create();
_.Options.BlockStyle = BlockStyle.CurlyBraces;
_.Options.IndentSize = 4;
_.Options.IndentChar = ' ';

_.L("using System.Text;");

_.L("namespace MyProgram").B(_ =>
{
    _.L("public class MyProgram").B(_ =>
    {
        _.L("public static void Main(string[] args)").B(_ =>
        {
            _.L("if (count > 6)").B(_ =>
            {
                _.L("Console.WriteLine(`Hello World!`);");
                _.L("Console.WriteLine(`Hello Again!`);");
            })
            .L("else").B(_ =>
            {
                _.L("Console.WriteLine(`Hello World!`);");
            });
        });
    });
});

Console.WriteLine(_.ToString());

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🐍 Python Example (IndentOnly)

var _ = TextBuilder.Create();
_.Options.BlockStyle = BlockStyle.IndentOnly;
_.Options.IndentSize = 4;
_.Options.IndentChar = ' ';

_.L("def greet():").B(_ =>
{
    _.L("print(`Hello World!`)");
    _.L("print(`Hello Again!`)");
});

Console.WriteLine(_.ToString());

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🌐 HTML Example

var _ = TextBuilder.Create();
_.Options.BlockStyle = BlockStyle.IndentOnly;
_.Options.IndentSize = 2;
_.Options.IndentChar = ' ';

_.L("<div>").B(_ =>
{
    _.L("<span>Hello World!</span>");
    _.L("<span>Hello Again!</span>");
}
).L("</div>");

Console.WriteLine(_.ToString());

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📄 XML Example

var _ = TextBuilder.Create();
_.Options.BlockStyle = BlockStyle.IndentOnly;
_.Options.IndentSize = 4;
_.Options.IndentChar = ' ';

_.L("<config>").B(_ =>
{
    _.L("<entry key=`theme`>dark</entry>");
    _.L("<entry key=`lang`>en</entry>");
}
).L("</config>");

Console.WriteLine(_.ToString());

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📘 YAML Example

var _ = TextBuilder.Create();
_.Options.BlockStyle = BlockStyle.IndentOnly;
_.Options.IndentSize = 4;
_.Options.IndentChar = ' ';

_.L("library:").B(_ =>
{
    _.L("name: `Nest`");
    _.L("use: `Structured Text Generation`");

    _.L("features:").B(_ =>
    {
        _.L("- Automated Indentation");
        _.L("- Easy To Use");
        _.L("- Zero Dependency");
    });
});

Console.WriteLine(_.ToString());

---

Debugging

You can inspect the builder at any point during generation:

_.L("if (count > 0)").B(_ =>
{
    _.L("Console.WriteLine(`Positive`);");

    Console.WriteLine("--- Debug Snapshot ---");
    Console.WriteLine(_.ToString()); // View current generated output
});

Alternatively, set a breakpoint anywhere and inspect the builder in your debugger. This is especially useful when checking structure, indentation, or formatting mid-flow.

Since everything is standard C#, you can step through and verify behavior interactively — no custom tooling needed.