Subliminal Nightfall

                                use std::fmt;
use std::result::Result;

/// Represents different types of HTTP methods
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum HttpMethod {
    Get,
    Post,
    Put,
    Delete,
    Patch,
}

/// Custom error types for our application
#[derive(Debug)]
pub enum AppError {
    NotFound(String),
    InvalidInput { field: String, message: String },
    DatabaseError(String),
    Unauthorized,
}

impl fmt::Display for AppError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            AppError::NotFound(msg) => write!(f, "Not found: {}", msg),
            AppError::InvalidInput { field, message } => {
                write!(f, "Invalid input for {}: {}", field, message)
            }
            AppError::DatabaseError(msg) => write!(f, "Database error: {}", msg),
            AppError::Unauthorized => write!(f, "Unauthorized access"),
        }
    }
}

/// A trait for serializable types
pub trait Serializable {
    fn serialize(&self) -> String;
    fn deserialize(data: &str) -> Result<Self, AppError>
    where
        Self: Sized;
}

/// User struct with lifetime annotations
#[derive(Debug, Clone)]
pub struct User<'a> {
    pub id: u64,
    pub username: &'a str,
    pub email: &'a str,
    pub age: Option<u8>,
    pub is_active: bool,
}

impl<'a> User<'a> {
    /// Creates a new user with validation
    pub fn new(id: u64, username: &'a str, email: &'a str) -> Result<Self, AppError> {
        if username.is_empty() {
            return Err(AppError::InvalidInput {
                field: "username".to_string(),
                message: "Username cannot be empty".to_string(),
            });
        }

        if !email.contains('@') {
            return Err(AppError::InvalidInput {
                field: "email".to_string(),
                message: "Invalid email format".to_string(),
            });
        }

        Ok(User {
            id,
            username,
            email,
            age: None,
            is_active: true,
        })
    }

    /// Updates the user's age
    pub fn set_age(&mut self, age: u8) -> Result<(), AppError> {
        if age > 150 {
            return Err(AppError::InvalidInput {
                field: "age".to_string(),
                message: "Age must be realistic".to_string(),
            });
        }
        self.age = Some(age);
        Ok(())
    }
}

/// Generic repository trait with associated types
pub trait Repository<T> {
    type Error;
    type Id;

    fn find(&self, id: Self::Id) -> Result<T, Self::Error>;
    fn save(&mut self, item: T) -> Result<Self::Id, Self::Error>;
    fn delete(&mut self, id: Self::Id) -> Result<(), Self::Error>;
}

/// Process a request with pattern matching
pub fn process_request(method: HttpMethod, path: &str) -> Result<String, AppError> {
    match (method, path) {
        (HttpMethod::Get, "/users") => Ok("List all users".to_string()),
        (HttpMethod::Get, path) if path.starts_with("/users/") => {
            let id = path.strip_prefix("/users/").unwrap_or("0");
            Ok(format!("Get user with id: {}", id))
        }
        (HttpMethod::Post, "/users") => Ok("Create new user".to_string()),
        (HttpMethod::Put, path) if path.starts_with("/users/") => Ok("Update user".to_string()),
        (HttpMethod::Delete, path) if path.starts_with("/users/") => Ok("Delete user".to_string()),
        _ => Err(AppError::NotFound(format!(
            "Route not found: {:?} {}",
            method, path
        ))),
    }
}

/// Macro for creating a user quickly
#[macro_export]
macro_rules! create_user {
    ($id:expr, $username:expr, $email:expr) => {
        User::new($id, $username, $email)
    };
    ($id:expr, $username:expr, $email:expr, age: $age:expr) => {{
        let mut user = User::new($id, $username, $email)?;
        user.set_age($age)?;
        Ok(user)
    }};
}

fn main() -> Result<(), AppError> {
    // Create a new user
    let mut user = User::new(1, "alice", "[email protected]")?;
    user.set_age(28)?;

    println!("Created user: {:?}", user);

    // Pattern matching with enums
    let methods = vec![
        HttpMethod::Get,
        HttpMethod::Post,
        HttpMethod::Put,
        HttpMethod::Delete,
    ];

    for method in methods {
        match method {
            HttpMethod::Get => println!("Handling GET request"),
            HttpMethod::Post => println!("Handling POST request"),
            HttpMethod::Put => println!("Handling PUT request"),
            HttpMethod::Delete => println!("Handling DELETE request"),
            HttpMethod::Patch => println!("Handling PATCH request"),
        }
    }

    // Process some requests
    let result = process_request(HttpMethod::Get, "/users")?;
    println!("Result: {}", result);

    // Option handling
    if let Some(age) = user.age {
        println!("User age: {}", age);
    } else {
        println!("Age not set");
    }

    Ok(())
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_user_creation() {
        let user = User::new(1, "test", "[email protected]");
        assert!(user.is_ok());
    }

    #[test]
    fn test_invalid_email() {
        let user = User::new(1, "test", "invalid-email");
        assert!(user.is_err());
    }

    #[test]
    fn test_age_validation() {
        let mut user = User::new(1, "test", "[email protected]").unwrap();
        assert!(user.set_age(200).is_err());
        assert!(user.set_age(25).is_ok());
    }
}

                            

                                // TypeScript Example - API Client with Generics and Async/Await

interface User {
  id: number;
  username: string;
  email: string;
  createdAt: Date;
  isActive: boolean;
}

interface Post {
  id: number;
  title: string;
  content: string;
  authorId: number;
  tags: string[];
  publishedAt?: Date;
}

// Generic API response wrapper
interface ApiResponse<T> {
  data: T;
  status: number;
  message?: string;
}

// Generic paginated response
interface PaginatedResponse<T> {
  items: T[];
  total: number;
  page: number;
  pageSize: number;
  hasNext: boolean;
}

// Custom error class
class ApiError extends Error {
  constructor(
    public statusCode: number,
    message: string,
    public details?: unknown
  ) {
    super(message);
    this.name = 'ApiError';
  }
}

// Generic repository interface with CRUD operations
interface Repository<T, ID = number> {
  findById(id: ID): Promise<T | null>;
  findAll(options?: QueryOptions): Promise<T[]>;
  create(data: Omit<T, 'id'>): Promise<T>;
  update(id: ID, data: Partial<T>): Promise<T>;
  delete(id: ID): Promise<void>;
}

interface QueryOptions {
  page?: number;
  limit?: number;
  sortBy?: string;
  sortOrder?: 'asc' | 'desc';
  filters?: Record<string, unknown>;
}

// API Client with generics
class ApiClient<T> {
  private baseUrl: string;
  private headers: Record<string, string>;

  constructor(baseUrl: string, token?: string) {
    this.baseUrl = baseUrl;
    this.headers = {
      'Content-Type': 'application/json',
      ...(token && { Authorization: `Bearer ${token}` }),
    };
  }

  async get<R = T>(endpoint: string): Promise<ApiResponse<R>> {
    try {
      const response = await fetch(`${this.baseUrl}${endpoint}`, {
        method: 'GET',
        headers: this.headers,
      });

      if (!response.ok) {
        throw new ApiError(
          response.status,
          `Failed to fetch: ${response.statusText}`
        );
      }

      const data = await response.json();
      return {
        data,
        status: response.status,
      };
    } catch (error) {
      if (error instanceof ApiError) {
        throw error;
      }
      throw new ApiError(500, 'Network error', error);
    }
  }

  async post<R = T>(endpoint: string, body: unknown): Promise<ApiResponse<R>> {
    const response = await fetch(`${this.baseUrl}${endpoint}`, {
      method: 'POST',
      headers: this.headers,
      body: JSON.stringify(body),
    });

    const data = await response.json();
    return { data, status: response.status };
  }

  async put<R = T>(endpoint: string, body: unknown): Promise<ApiResponse<R>> {
    const response = await fetch(`${this.baseUrl}${endpoint}`, {
      method: 'PUT',
      headers: this.headers,
      body: JSON.stringify(body),
    });

    const data = await response.json();
    return { data, status: response.status };
  }

  async delete(endpoint: string): Promise<void> {
    await fetch(`${this.baseUrl}${endpoint}`, {
      method: 'DELETE',
      headers: this.headers,
    });
  }
}

// User service with type-safe methods
class UserService {
  private client: ApiClient<User>;

  constructor(baseUrl: string, token?: string) {
    this.client = new ApiClient<User>(baseUrl, token);
  }

  async getUser(id: number): Promise<User | null> {
    try {
      const response = await this.client.get<User>(`/users/${id}`);
      return response.data;
    } catch (error) {
      if (error instanceof ApiError && error.statusCode === 404) {
        return null;
      }
      throw error;
    }
  }

  async createUser(userData: Omit<User, 'id' | 'createdAt'>): Promise<User> {
    const response = await this.client.post<User>('/users', {
      ...userData,
      createdAt: new Date(),
    });
    return response.data;
  }

  async updateUser(id: number, updates: Partial<User>): Promise<User> {
    const response = await this.client.put<User>(`/users/${id}`, updates);
    return response.data;
  }

  async deleteUser(id: number): Promise<void> {
    await this.client.delete(`/users/${id}`);
  }

  async searchUsers(query: string): Promise<User[]> {
    const response = await this.client.get<User[]>(
      `/users/search?q=${encodeURIComponent(query)}`
    );
    return response.data;
  }
}

// Utility type helpers
type DeepPartial<T> = {
  [P in keyof T]?: T[P] extends object ? DeepPartial<T[P]> : T[P];
};

type ReadOnly<T> = {
  readonly [P in keyof T]: T[P];
};

// Advanced async patterns
async function processUsersBatch(
  userIds: number[],
  service: UserService
): Promise<User[]> {
  const userPromises = userIds.map((id) => service.getUser(id));

  // Process all requests in parallel
  const results = await Promise.allSettled(userPromises);

  // Filter successful results
  return results
    .filter((result): result is PromiseFulfilledResult<User> =>
      result.status === 'fulfilled' && result.value !== null
    )
    .map((result) => result.value);
}

// Retry logic with exponential backoff
async function withRetry<T>(
  fn: () => Promise<T>,
  maxRetries = 3,
  delay = 1000
): Promise<T> {
  let lastError: Error | undefined;

  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fn();
    } catch (error) {
      lastError = error as Error;
      if (i < maxRetries - 1) {
        await new Promise((resolve) => setTimeout(resolve, delay * 2 ** i));
      }
    }
  }

  throw lastError || new Error('Max retries reached');
}

// Example usage
async function main() {
  const service = new UserService('https://api.example.com', 'my-token');

  try {
    // Create a new user
    const newUser = await service.createUser({
      username: 'johndoe',
      email: '[email protected]',
      isActive: true,
    });
    console.log('Created user:', newUser);

    // Get user with retry
    const user = await withRetry(() => service.getUser(newUser.id));
    console.log('Fetched user:', user);

    // Process multiple users
    const users = await processUsersBatch([1, 2, 3, 4, 5], service);
    console.log(`Processed ${users.length} users`);

    // Update user
    if (user) {
      const updated = await service.updateUser(user.id, {
        isActive: false,
      });
      console.log('Updated user:', updated);
    }
  } catch (error) {
    if (error instanceof ApiError) {
      console.error(`API Error ${error.statusCode}:`, error.message);
    } else {
      console.error('Unexpected error:', error);
    }
  }
}

// Export for use in other modules
export type {
  User,
  Post,
  ApiResponse,
  PaginatedResponse,
  Repository,
};

export {
  ApiError,
  ApiClient,
  UserService,
  processUsersBatch,
  withRetry,
};

                            

                                import Combine
import SwiftUI

// MARK: - Models

/// User model with Codable conformance
struct User: Identifiable, Codable, Equatable {
    let id: UUID
    var username: String
    var email: String
    var profileImageURL: URL?
    var createdAt: Date
    var isActive: Bool

    enum CodingKeys: String, CodingKey {
        case id
        case username
        case email
        case profileImageURL = "profile_image_url"
        case createdAt = "created_at"
        case isActive = "is_active"
    }
}

/// Post model with optional published date
struct Post: Identifiable, Codable {
    let id: UUID
    var title: String
    var content: String
    var authorId: UUID
    var tags: [String]
    var publishedAt: Date?
    var likes: Int

    var isPublished: Bool {
        publishedAt != nil
    }
}

// MARK: - Protocols

/// Protocol for API-fetchable resources
protocol Fetchable {
    associatedtype ID: Hashable
    var id: ID { get }
}

/// Repository protocol with generic type constraints
protocol Repository {
    associatedtype Item: Fetchable

    func fetch(id: Item.ID) async throws -> Item
    func fetchAll() async throws -> [Item]
    func create(_ item: Item) async throws -> Item
    func update(_ item: Item) async throws -> Item
    func delete(id: Item.ID) async throws
}

// MARK: - Errors

enum APIError: Error, LocalizedError {
    case networkError(Error)
    case invalidResponse
    case notFound
    case unauthorized
    case serverError(statusCode: Int)
    case decodingError(Error)

    var errorDescription: String? {
        switch self {
        case .networkError(let error):
            return "Network error: \(error.localizedDescription)"
        case .invalidResponse:
            return "Invalid response from server"
        case .notFound:
            return "Resource not found"
        case .unauthorized:
            return "Unauthorized access"
        case .serverError(let code):
            return "Server error with status code: \(code)"
        case .decodingError(let error):
            return "Failed to decode response: \(error.localizedDescription)"
        }
    }
}

// MARK: - API Client

class APIClient: ObservableObject {
    @Published var isLoading = false
    @Published var error: APIError?

    private let baseURL: URL
    private let session: URLSession

    init(baseURL: URL, session: URLSession = .shared) {
        self.baseURL = baseURL
        self.session = session
    }

    func request<T: Decodable>(
        endpoint: String,
        method: HTTPMethod = .get,
        body: Encodable? = nil
    ) async throws -> T {
        var request = URLRequest(url: baseURL.appendingPathComponent(endpoint))
        request.httpMethod = method.rawValue
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")

        if let body = body {
            request.httpBody = try JSONEncoder().encode(body)
        }

        do {
            let (data, response) = try await session.data(for: request)

            guard let httpResponse = response as? HTTPURLResponse else {
                throw APIError.invalidResponse
            }

            guard (200...299).contains(httpResponse.statusCode) else {
                throw APIError.serverError(statusCode: httpResponse.statusCode)
            }

            let decoder = JSONDecoder()
            decoder.dateDecodingStrategy = .iso8601
            return try decoder.decode(T.self, from: data)
        } catch let error as APIError {
            throw error
        } catch let error as DecodingError {
            throw APIError.decodingError(error)
        } catch {
            throw APIError.networkError(error)
        }
    }
}

enum HTTPMethod: String {
    case get = "GET"
    case post = "POST"
    case put = "PUT"
    case delete = "DELETE"
    case patch = "PATCH"
}

// MARK: - User Service

@MainActor
class UserService: ObservableObject {
    @Published var users: [User] = []
    @Published var currentUser: User?
    @Published var isLoading = false

    private let apiClient: APIClient

    init(apiClient: APIClient) {
        self.apiClient = apiClient
    }

    func fetchUser(id: UUID) async throws -> User {
        isLoading = true
        defer { isLoading = false }

        let user: User = try await apiClient.request(endpoint: "users/\(id.uuidString)")
        return user
    }

    func createUser(username: String, email: String) async throws -> User {
        let newUser = User(
            id: UUID(),
            username: username,
            email: email,
            profileImageURL: nil,
            createdAt: Date(),
            isActive: true
        )

        let created: User = try await apiClient.request(
            endpoint: "users",
            method: .post,
            body: newUser
        )
        users.append(created)
        return created
    }

    func updateUser(_ user: User) async throws {
        let updated: User = try await apiClient.request(
            endpoint: "users/\(user.id.uuidString)",
            method: .put,
            body: user
        )

        if let index = users.firstIndex(where: { $0.id == updated.id }) {
            users[index] = updated
        }
    }
}

// MARK: - SwiftUI Views

struct UserListView: View {
    @StateObject private var userService: UserService
    @State private var selectedUser: User?
    @State private var showError = false

    init(apiClient: APIClient) {
        _userService = StateObject(wrappedValue: UserService(apiClient: apiClient))
    }

    var body: some View {
        NavigationView {
            List(userService.users) { user in
                UserRowView(user: user)
                    .onTapGesture {
                        selectedUser = user
                    }
            }
            .navigationTitle("Users")
            .toolbar {
                ToolbarItem(placement: .primaryAction) {
                    Button(action: addUser) {
                        Image(systemName: "plus")
                    }
                }
            }
            .sheet(item: $selectedUser) { user in
                UserDetailView(user: user)
            }
        }
    }

    private func addUser() {
        Task {
            do {
                _ = try await userService.createUser(
                    username: "newuser",
                    email: "[email protected]"
                )
            } catch {
                showError = true
            }
        }
    }
}

struct UserRowView: View {
    let user: User

    var body: some View {
        HStack(spacing: 12) {
            // Profile image with optional handling
            if let imageURL = user.profileImageURL {
                AsyncImage(url: imageURL) { image in
                    image
                        .resizable()
                        .aspectRatio(contentMode: .fill)
                } placeholder: {
                    ProgressView()
                }
                .frame(width: 50, height: 50)
                .clipShape(Circle())
            } else {
                Circle()
                    .fill(Color.gray.opacity(0.3))
                    .frame(width: 50, height: 50)
                    .overlay(
                        Text(user.username.prefix(1))
                            .font(.title2)
                            .foregroundColor(.white)
                    )
            }

            VStack(alignment: .leading, spacing: 4) {
                Text(user.username)
                    .font(.headline)

                Text(user.email)
                    .font(.subheadline)
                    .foregroundColor(.secondary)
            }

            Spacer()

            if user.isActive {
                Circle()
                    .fill(Color.green)
                    .frame(width: 8, height: 8)
            }
        }
        .padding(.vertical, 4)
    }
}

struct UserDetailView: View {
    let user: User
    @Environment(\.dismiss) private var dismiss

    var body: some View {
        NavigationView {
            Form {
                Section("Profile") {
                    LabeledContent("Username", value: user.username)
                    LabeledContent("Email", value: user.email)
                    LabeledContent("Status", value: user.isActive ? "Active" : "Inactive")
                }

                Section("Details") {
                    LabeledContent("User ID", value: user.id.uuidString)
                    LabeledContent("Created", value: user.createdAt.formatted())
                }
            }
            .navigationTitle("User Details")
            .toolbar {
                ToolbarItem(placement: .confirmationAction) {
                    Button("Done") {
                        dismiss()
                    }
                }
            }
        }
    }
}

// MARK: - Preview Provider

#Preview {
    let mockClient = APIClient(baseURL: URL(string: "https://api.example.com")!)
    return UserListView(apiClient: mockClient)
}

                            

                                #!/bin/bash

# Terminal Example - Git workflow and system commands

# Color codes for terminal output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
MAGENTA='\033[0;35m'
CYAN='\033[0;36m'
NC='\033[0m' # No Color

echo -e "${CYAN}=== Git Status ===${NC}"
git status

# Output:
# On branch main
# Your branch is up to date with 'origin/main'.
#
# Changes to be committed:
#   (use "git restore --staged <file>..." to unstage)
#         modified:   src/components/Header.tsx
#         new file:   src/utils/api.ts
#
# Changes not staged for commit:
#   (use "git add <file>..." to update what will be committed)
#   (use "git restore <file>..." to discard changes in working directory)
#         modified:   README.md
#
# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#         .env.local

echo -e "\n${BLUE}=== Git Log ===${NC}"
git log --oneline -5

# Output:
# a1b2c3d (HEAD -> main) feat: add user authentication
# e4f5g6h feat: implement API client
# i7j8k9l fix: resolve routing bug
# m0n1o2p docs: update README
# q3r4s5t refactor: clean up components

echo -e "\n${GREEN}=== Directory Listing ===${NC}"
ls -lah

# Output:
# total 48K
# drwxr-xr-x  8 user user 4.0K Jan 15 10:30 .
# drwxr-xr-x 12 user user 4.0K Jan 15 09:15 ..
# drwxr-xr-x  2 user user 4.0K Jan 15 10:25 dist
# -rw-r--r--  1 user user  156 Jan 15 09:30 .gitignore
# drwxr-xr-x  8 user user 4.0K Jan 15 10:30 node_modules
# -rw-r--r--  1 user user 2.1K Jan 15 10:15 package.json
# -rw-r--r--  1 user user  12K Jan 15 10:15 package-lock.json
# -rw-r--r--  1 user user 1.5K Jan 15 09:45 README.md
# drwxr-xr-x  5 user user 4.0K Jan 15 10:20 src

echo -e "\n${YELLOW}=== Running Tests ===${NC}"
npm test

# Output:
# > [email protected] test
# > jest
#
# PASS  src/utils/api.test.ts
#   ✓ should fetch users successfully (15ms)
#   ✓ should handle errors correctly (8ms)
#   ✓ should retry on network failure (25ms)
#
# PASS  src/components/UserList.test.tsx
#   ✓ renders user list correctly (42ms)
#   ✓ handles empty state (18ms)
#   ✓ filters users by search query (31ms)
#
# Test Suites: 2 passed, 2 total
# Tests:       6 passed, 6 total
# Snapshots:   0 total
# Time:        3.456s

echo -e "\n${MAGENTA}=== System Information ===${NC}"
uname -a

# Output:
# Darwin MacBook-Pro.local 23.2.0 Darwin Kernel Version 23.2.0
# x86_64 i386 MacBookPro16,1 Darwin

echo -e "\n${CYAN}=== Process Status ===${NC}"
ps aux | head -n 5

# Output:
# USER   PID  %CPU %MEM      VSZ    RSS   TT  STAT STARTED      TIME COMMAND
# user  1234  15.2  2.1  5432100 345678   ??  S    10:15AM   1:23.45 /Applications/Code.app
# user  5678   8.3  1.5  3210000 234567   ??  S    10:20AM   0:45.12 node server.js
# user  9012   2.1  0.8  1234567 123456   ??  S    10:25AM   0:12.34 npm run dev
# user  3456   0.5  0.3   654321  45678 s001  S    10:30AM   0:03.21 bash

echo -e "\n${GREEN}=== Building Project ===${NC}"
npm run build

# Output:
# > [email protected] build
# > astro build
#
# 14:32:15 [content] Types generated 158ms
# 14:32:15 [build] output: "static"
# 14:32:15 [build] directory: /Users/user/project/dist/
# 14:32:15 [build] Collecting build info...
# 14:32:16 [build] ✓ Completed in 1.23s.
# 14:32:16 [build] Building static entrypoints...
# 14:32:18 [build] ✓ Completed in 2.45s.
#
# @astrojs/sitemap: Generated sitemap
#
# ✓ Built in 3.68s

echo -e "\n${RED}=== Error Example ===${NC}"
# This command will fail
cat nonexistent-file.txt 2>&1

# Output:
# cat: nonexistent-file.txt: No such file or directory

echo -e "\n${BLUE}=== Network Request ===${NC}"
curl -s https://api.github.com/users/mhamrah | jq '.name, .bio'

# Output:
# "Michael Hamrah"
# "Software Engineer | Open Source Enthusiast"

echo -e "\n${GREEN}=== Success Message ===${NC}"
echo "✓ All operations completed successfully!"