FunctionalDdd.CommonValueObjectGenerator 3.0.0-alpha.20

CommonValueObjectGenerator

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>
// - NewUnique() method for new 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 FunctionalDDD.CommonValueObjects:

dotnet add package FunctionalDDD.CommonValueObjects

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

Generated API

For RequiredString Classes

public partial class ProductName : RequiredString
{
}

// 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 Classes

public partial class UserId : RequiredGuid
{
}

// Generated members:
UserId.NewUnique()                                       // New 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 FunctionalDDD.CommonValueObjects package

How It Works

1. Analyzes your code for partial classes inheriting from RequiredString or RequiredGuid
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 ? FunctionalDdd.CommonValueObjectGenerator
• Output: obj/Debug/net10.0/generated/

Resources

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

License

MIT � Xavier John