v0.1.0 to v0.1.0

---

name: coding-csharp

version: 0.1.0

description: C# naming conventions, async/await patterns, interface conventions, and quality overrides for ECHO Protocol.

---

# C# Coding Standards

<!-- Load this when protocol.config.yaml has language: "csharp" -->

## Naming Conventions

| Element | Convention | Example |

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

| Classes | PascalCase | `UserProfile`, `GameState` |

| Interfaces | PascalCase (I prefix) | `ISerializable`, `IRenderable` |

| Methods | PascalCase | `CalculateDistance`, `SpawnUnit` |

| Variables (public) | PascalCase | `PlayerCount`, `IsValid` |

| Variables (private) | camelCase | `playerCount`, `isValid` |

| Constants | PascalCase | `MaxPlayers`, `TileSize` |

| Static fields | s_ prefix (private), PascalCase (public) | `s_instance`, `Config` |

| Enums | PascalCase (type), PascalCase (values) | `TileType.Grassland` |

| Namespaces | PascalCase | `GameEngine.WorldGen` |

| Files | PascalCase.cs (match class name) | `UserProfile.cs` |

## Patterns

### Error Handling

- Use custom exception hierarchy extending `Exception`

- Catch specific exceptions, never bare `Exception`

- Use `IDisposable` with `using` statements

- Prefer `Result<T>` pattern over exceptions for expected failures

### Async/Await

- Use `async/await` consistently, avoid `.Result` or `.Wait()`

- Pass `CancellationToken` through async chains

- Use `ConfigureAwait(false)` in library code

- Avoid `async void` except for event handlers

### Imports

- Group: System → external → internal

- Use `using` directives at file top

- Prefer `using static` for utility methods

## File Structure

```text

src/

├── Program.cs # Entry point

├── Config/

│ └── AppConfig.cs # Configuration

├── Exceptions/

│ └── AppException.cs # Custom exceptions

├── Models/

│ └── [Domain].cs # Data classes

├── Services/

│ └── [Domain]Service.cs # Business logic

tests/

└── [Mirror structure]

```

## Anti-Patterns to Flag

- [ ] `catch (Exception e)` without rethrow

- [ ] `async void` methods

- [ ] `.Result` or `.Wait()` on tasks

- [ ] Mutable static state

- [ ] Magic numbers (extract to constants)

- [ ] `var` when type is not obvious from context