Trellis.Primitives.Generator 3.0.0-alpha.98

Trellis.Primitives.Generator

Roslyn source generator for creating strongly-typed value objects with automatic validation and IParsable support.

What It Does

Automatically generates boilerplate code for classes inheriting from RequiredString or RequiredGuid:

// You write this:
public partial class OrderId : RequiredGuid
{
}

// Generator creates:
// - TryCreate(Guid?) method returning Result<OrderId>
// - TryCreate(string?) method returning Result<OrderId>
// - NewUniqueV4() method for new GUIDs
// - NewUniqueV7() method for time-ordered GUIDs
// - Parse(string, IFormatProvider?) method (IParsable)
// - TryParse(string?, IFormatProvider?, out OrderId) method (IParsable)
// - Explicit cast operator from Guid
// - Validation error messages

Installation

This package is included automatically when you install Trellis.Primitives:

dotnet add package Trellis.Primitives

Note: Both packages are required - the main package provides base classes, this generator creates the implementations.

Generated API

For RequiredString<TSelf> Classes

public partial class ProductName : RequiredString<ProductName>
{
}

// Generated members:
ProductName.TryCreate(string?)                           // Result<ProductName>
ProductName.Parse(string, IFormatProvider?)              // ProductName (throws)
ProductName.TryParse(string?, IFormatProvider?, out...)  // bool
(ProductName)"ABC"                                       // Explicit cast

For RequiredGuid<TSelf> Classes

public partial class UserId : RequiredGuid<UserId>
{
}

// Generated members:
UserId.NewUniqueV4()                                    // New random GUID
UserId.NewUniqueV7()                                    // New time-ordered GUID
UserId.TryCreate(Guid?)                                  // Result<UserId>
UserId.TryCreate(string?)                                // Result<UserId>
UserId.Parse(string, IFormatProvider?)                   // UserId (throws)
UserId.TryParse(string?, IFormatProvider?, out...)       // bool
(UserId)Guid.NewGuid()                                   // Explicit cast

Requirements

• .NET Standard 2.0 compatible (source generators must target netstandard2.0)
• C# 9.0+ for partial class support
• Requires Trellis.Primitives package

How It Works

1. Analyzes your code for partial classes inheriting from RequiredString<TSelf> or RequiredGuid<TSelf>
2. Generates implementation code at compile-time
3. Code appears in IntelliSense automatically
4. No runtime reflection - all compile-time

Validation

Generated code includes automatic validation:

var result = ProductName.TryCreate("");  
// Returns: Result.Failure("Product Name cannot be empty.")

var result = UserId.TryCreate(Guid.Empty);
// Returns: Result.Failure("User Id cannot be empty.")

Error messages use the class name (e.g., "Product Name" from "ProductName").

Source Code

This is a source generator - it runs at compile-time and generates C# code. The generated code is visible in:

• Visual Studio: Project → Dependencies → Analyzers → Trellis.Primitives.Generator
• Output: obj/Debug/net10.0/generated/

Resources

• Main Library Documentation
• Value Objects Guide
• Complete Examples
• GitHub Repository

License

MIT © Xavier John