Comments are notes for humans<\/strong> \u2014 the compiler completely ignores them.<\/p>\n Main reasons people write comments:<\/p>\n Most common style \u2014 used everywhere.<\/p>\n Very common patterns:<\/strong><\/p>\n Used less often, but still important in specific cases.<\/p>\n Realistic examples where people actually use \/* *\/:<\/strong><\/p>\n Xcode shows these in the jump bar (the dropdown above the editor).<\/p>\n You can also add a separator line:<\/p>\n These generate beautiful documentation<\/strong> when you Option-click a symbol in Xcode.<\/p>\n When someone Option-clicks this function in Xcode, they see:<\/p>\n Very professional \u2014 almost every public function in good libraries uses \/\/\/.<\/p>\n Most people now prefer \/\/\/ because it’s cleaner.<\/p>\n Good habits:<\/strong><\/p>\n Bad habits (please avoid):<\/strong><\/p>\n Example 1 \u2013 Clean function documentation<\/strong><\/p>\n Example 2 \u2013 Organized struct<\/strong><\/p>\n Would you like to continue with:<\/p>\n Just tell me what you\u2019d like next \u2014 we\u2019ll keep the same detailed, teacher-like style \ud83d\ude0a<\/p>\n","protected":false},"excerpt":{"rendered":" 1. Why do we write comments at all? Comments are notes for humans \u2014 the compiler completely ignores them. Main reasons people write comments: Explain why something is done (not just what) Document public...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[76],"tags":[],"class_list":["post-2596","post","type-post","status-publish","format-standard","hentry","category-swift"],"_links":{"self":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2596","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/comments?post=2596"}],"version-history":[{"count":1,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2596\/revisions"}],"predecessor-version":[{"id":2597,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2596\/revisions\/2597"}],"wp:attachment":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/media?parent=2596"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/categories?post=2596"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/tags?post=2596"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\n
2. The two main types of comments in Swift<\/h3>\n
Type A: Single-line comment \u2014 \/\/<\/h4>\n
\/\/ This is a single-line comment\r\n\r\nlet name = \"Priya\" \/\/ inline comment after code\r\n\r\n\/\/ You can write as many lines as you want\r\n\/\/ each starting with \/\/<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\/\/ MARK: - View Life Cycle\r\noverride func viewDidLoad() {\r\n super.viewDidLoad()\r\n \/\/ Do any additional setup after loading the view.\r\n}\r\n\r\n\/\/ Configuration\r\nprivate func setupUI() {\r\n \/\/ Colors\r\n backgroundColor = .systemBackground\r\n \r\n \/\/ Fonts\r\n titleLabel.font = .preferredFont(forTextStyle: .headline)\r\n \r\n \/\/ Layout constraints\r\n NSLayoutConstraint.activate([\r\n \/\/ ...\r\n ])\r\n}\r\n\r\n\/\/ TODO: Handle offline mode later\r\n\/\/ FIXME: This calculation is wrong on leap years\r\n\/\/ WARNING: Do not call this on main thread!<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nType B: Multi-line comment \u2014 \/* … *\/<\/h4>\n
\/*\r\nThis is a multi-line comment.\r\nIt can span several lines.\r\nVery useful for longer explanations.\r\n*\/<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\/*\r\n JSON response structure from API:\r\n {\r\n \"user\": {\r\n \"id\": 1234,\r\n \"name\": \"Aarav\",\r\n \"email\": \"aarav@example.com\"\r\n },\r\n \"token\": \"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...\"\r\n }\r\n*\/<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\/* \r\n \u2554\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2557\r\n \u2551 IMPORTANT NOTICE \u2551\r\n \u2551 \u2551\r\n \u2551 Never commit real API keys to git! \u2551\r\n \u2551 Use environment variables or Secrets. \u2551\r\n \u255a\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u255d\r\n*\/<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n3. Special comment styles that modern Swift developers love<\/h3>\n
3.1 \/\/ MARK: \u2013 Section headers (very very common in Xcode)<\/h4>\n
\/\/ MARK: - Properties\r\n\r\nprivate let apiClient = APIClient()\r\nprivate var userSession: UserSession?\r\n\r\n\/\/ MARK: - Public Methods\r\n\r\nfunc login(email: String, password: String) async throws {\r\n \/\/ ...\r\n}\r\n\r\n\/\/ MARK: - Private Helpers\r\n\r\nprivate func validateInput() -> Bool {\r\n \/\/ ...\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\/\/ MARK: - View Life Cycle -----------------------------------<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n3.2 Documentation comments \u2014 \/\/\/ (super important!)<\/h4>\n
\/\/\/ Calculates the total price including tax.\r\n\/\/\/\r\n\/\/\/ - Parameters:\r\n\/\/\/ - subtotal: The price before tax (must be positive)\r\n\/\/\/ - taxRate: Tax rate as a percentage (0...100)\r\n\/\/\/ - Returns: The final amount to pay\r\n\/\/\/ - Throws: `PricingError.negativeSubtotal` if subtotal is negative\r\nfunc calculateTotal(subtotal: Double, taxRate: Double) throws -> Double {\r\n guard subtotal >= 0 else {\r\n throw PricingError.negativeSubtotal\r\n }\r\n \r\n let tax = subtotal * (taxRate \/ 100)\r\n return subtotal + tax\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n
3.3 \/** … *\/ \u2014 old-style doc comments (still works, less common now)<\/h4>\n
\/**\r\n Calculates the area of a circle.\r\n \r\n - parameter radius: The radius of the circle\r\n - returns: Area in square units\r\n *\/\r\nfunc circleArea(radius: Double) -> Double {\r\n return .pi * radius * radius\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n4. Good habits & bad habits (real developer advice)<\/h3>\n
\n
\/\/ bad: useless comment\r\nlet x = 10 \/\/ set x to 10\r\n\r\n\/\/ bad: comment that just repeats the code\r\nuser.age = user.age + 1 \/\/ increase age by 1\r\n\r\n\/\/ bad: lying comment (very dangerous!)\r\nlet isAdmin = true \/\/ only for testing<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n5. Quick reference table \u2013 when to use each style<\/h3>\n
\n\n
\n \nStyle<\/th>\n Syntax<\/th>\n Best used for<\/th>\n Frequency in modern code<\/th>\n<\/tr>\n<\/thead>\n \n \/\/<\/td>\n Single line<\/td>\n inline notes, temporary disable, TODO\/FIXME<\/td>\n \u2605\u2605\u2605\u2605\u2605 (most common)<\/td>\n<\/tr>\n \n \/\/ MARK:<\/td>\n Section header<\/td>\n organizing code in files (shows in Xcode jump bar)<\/td>\n \u2605\u2605\u2605\u2605\u2605<\/td>\n<\/tr>\n \n \/\/\/<\/td>\n Documentation<\/td>\n public API, functions, structs, properties<\/td>\n \u2605\u2605\u2605\u2605 (very important)<\/td>\n<\/tr>\n \n \/* … *\/<\/td>\n Multi-line block<\/td>\n long explanations, ASCII art notices, JSON examples<\/td>\n \u2605\u2605 (occasional)<\/td>\n<\/tr>\n \n \/** … *\/<\/td>\n Old doc block<\/td>\n legacy code or some open-source projects<\/td>\n \u2605 (rare now)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n 6. Small realistic examples you can copy-paste<\/h3>\n
\/\/\/ Formats a phone number into international style.\r\n\/\/\/\r\n\/\/\/ Example: \"9876543210\" \u2192 \"+91 98765 43210\"\r\n\/\/\/\r\n\/\/\/ - Parameter rawNumber: Raw Indian phone number (10 digits)\r\n\/\/\/ - Returns: Formatted string or nil if invalid\r\nfunc formatIndianPhoneNumber(_ rawNumber: String) -> String? {\r\n \/\/ Remove all non-digits\r\n let digits = rawNumber.filter { $0.isNumber }\r\n \r\n \/\/ Check length\r\n guard digits.count == 10 else { return nil }\r\n \r\n \/\/ Format: +91 XXXXX XXXXX\r\n let prefix = \"+91 \"\r\n let part1 = String(digits.prefix(5))\r\n let part2 = String(digits.dropFirst(5))\r\n \r\n return prefix + part1 + \" \" + part2\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\/\/ MARK: - Models\r\n\r\nstruct UserProfile {\r\n \/\/ MARK: - Properties\r\n \r\n let id: UUID\r\n var name: String\r\n var email: String?\r\n \r\n \/\/ MARK: - Computed Properties\r\n \r\n var displayName: String {\r\n name.trimmingCharacters(in: .whitespacesAndNewlines)\r\n }\r\n \r\n \/\/ MARK: - Initialization\r\n \r\n init(id: UUID = UUID(), name: String, email: String? = nil) {\r\n self.id = id\r\n self.name = name\r\n self.email = email\r\n }\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n