When you have an array, you usually want to:<\/p>\n
Swift gives you several very elegant ways to do this \u2014 and choosing the right one makes your code clearer, safer, and more efficient<\/strong>.<\/p>\n When to use this:<\/strong><\/p>\n Real-life example \u2013 show list of tasks<\/strong><\/p>\n This is the most common way when you need both the item and its position<\/strong>.<\/p>\n Output:<\/strong><\/p>\n Real-life example \u2013 numbered list in console or debug log<\/strong><\/p>\n Use this when you mainly need the positions<\/strong> and will access the array manually.<\/p>\n When to use this style:<\/strong><\/p>\n Key differences from for-in:<\/strong><\/p>\n Realistic use case \u2013 small logging or side effects<\/strong><\/p>\n These are advanced but very common in real apps today.<\/p>\n (We\u2019ll cover async loops later \u2014 just showing it exists.)<\/p>\n Paste your code if you want feedback or improvements!<\/p>\n What would you like to explore next about arrays?<\/p>\n Just tell me \u2014 we\u2019ll keep going in the same clear, detailed, teacher-like style \ud83d\ude0a<\/p>\n","protected":false},"excerpt":{"rendered":" 1. Why do we need different ways to loop? When you have an array, you usually want to: Do something with each item Know the position (index) of each item Transform items into a...<\/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-2659","post","type-post","status-publish","format-standard","hentry","category-swift"],"_links":{"self":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2659","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=2659"}],"version-history":[{"count":1,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2659\/revisions"}],"predecessor-version":[{"id":2660,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2659\/revisions\/2660"}],"wp:attachment":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/media?parent=2659"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/categories?post=2659"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/tags?post=2659"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}2. The 5 most important ways to loop over arrays<\/h3>\n
Way 1 \u2013 Simple for-in loop (most common & most readable)<\/h4>\n
let fruits = [\"Mango\", \"Banana\", \"Apple\", \"Orange\", \"Guava\"]\r\n\r\nfor fruit in fruits {\r\n print(\"I like \\(fruit)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n
let tasks = [\"Buy groceries\", \"Finish report\", \"Call mom\", \"Gym\"]\r\n\r\nprint(\"Today's tasks:\")\r\nfor task in tasks {\r\n print(\"\u2022 \\(task)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nWay 2 \u2013 for-in with index using enumerated()<\/h4>\n
let fruits = [\"Mango\", \"Banana\", \"Apple\", \"Orange\"]\r\n\r\nfor (index, fruit) in fruits.enumerated() {\r\n print(\"\\(index + 1). \\(fruit)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n1. Mango\r\n2. Banana\r\n3. Apple\r\n4. Orange<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nlet logs = [\r\n \"User logged in\",\r\n \"API call failed\",\r\n \"Retry successful\",\r\n \"Session ended\"\r\n]\r\n\r\nprint(\"Recent activity:\")\r\nfor (i, log) in logs.enumerated() {\r\n print(\" [\\(i + 1)] \\(log)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nWay 3 \u2013 Loop over indices only (indices property)<\/h4>\n
let scores = [85, 92, 78, 95, 88]\r\n\r\nfor index in scores.indices {\r\n let score = scores[index]\r\n let grade = score >= 90 ? \"A\" : score >= 80 ? \"B\" : \"C\"\r\n print(\"Student \\(index + 1): \\(grade)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n
Way 4 \u2013 forEach method (functional style)<\/h4>\n
let fruits = [\"Mango\", \"Banana\", \"Apple\"]\r\n\r\nfruits.forEach { fruit in\r\n print(\"\u2192 I like \\(fruit)\")\r\n}\r\n\r\n\/\/ or shorter with implicit $0\r\nfruits.forEach {\r\n print(\"\u2192 I like \\($0)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n
let recentSearches = [\"Swift arrays\", \"String interpolation\", \"forEach vs for-in\"]\r\n\r\nrecentSearches.forEach { query in\r\n print(\"User searched: \\(query)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nWay 5 \u2013 Modern for try or for await (when dealing with throwing or async items)<\/h4>\n
\/\/ Example with throwing functions\r\nlet urls = [\r\n URL(string: \"https:\/\/example.com\/1\")!,\r\n URL(string: \"https:\/\/example.com\/2\")!\r\n]\r\n\r\nfor try await data in urls.asyncMap({ try await URLSession.shared.data(from: $0).0 }) {\r\n print(\"Downloaded data of size: \\(data.count) bytes\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n6. Very Common Real-Life Examples<\/h3>\n
Example 1 \u2013 Display numbered list in console or debug<\/h4>\n
let recentMessages = [\r\n \"Hey, how are you?\",\r\n \"Meeting at 3 PM\",\r\n \"Sent you the file\",\r\n \"Thanks!\"\r\n]\r\n\r\nprint(\"Recent messages:\")\r\nfor (index, message) in recentMessages.enumerated() {\r\n print(\" \\(index + 1). \\(message)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nExample 2 \u2013 Process items with position<\/h4>\n
let items = [\"Phone\", \"Charger\", \"Case\", \"Screen guard\"]\r\n\r\nvar totalPrice: Double = 0\r\nvar receipt = \"Receipt:\\n\"\r\n\r\nfor (index, item) in items.enumerated() {\r\n let price: Double\r\n switch item {\r\n case \"Phone\": price = 74999\r\n case \"Charger\": price = 1999\r\n case \"Case\": price = 999\r\n case \"Screen guard\": price = 499\r\n default: price = 0\r\n }\r\n \r\n totalPrice += price\r\n receipt += \" \\(index + 1). \\(item) - \u20b9\\(price)\\n\"\r\n}\r\n\r\nreceipt += \"-------------------\\n\"\r\nreceipt += \"Total: \u20b9\\(totalPrice)\"\r\n\r\nprint(receipt)<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\nExample 3 \u2013 Filter & transform with forEach (functional style)<\/h4>\n
let temperatures = [28.5, 32.1, 35.8, 29.4, 31.2]\r\n\r\ntemperatures.forEach { temp in\r\n let status = temp > 32 ? \"Hot \u2600\ufe0f\" : temp < 30 ? \"Pleasant \ud83c\udf24\ufe0f\" : \"Warm \ud83d\ude05\"\r\n print(\"\\(temp)\u00b0C \u2192 \\(status)\")\r\n}<\/code><\/pre>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n7. Quick Summary \u2013 Which Loop Style to Choose<\/h3>\n
\n\n
\n \nSituation<\/th>\n Recommended style<\/th>\n Why \/ when to prefer it<\/th>\n<\/tr>\n<\/thead>\n \n Just process each item (no index needed)<\/td>\n for item in array { \u2026 }<\/td>\n Simplest, most readable<\/td>\n<\/tr>\n \n Need the position (index)<\/td>\n for (index, item) in array.enumerated()<\/td>\n Most common when showing numbered lists<\/td>\n<\/tr>\n \n Only need indices (rare)<\/td>\n for index in array.indices { \u2026 }<\/td>\n When modifying or using multiple arrays<\/td>\n<\/tr>\n \n Functional style, chaining, side effects<\/td>\n array.forEach { \u2026 }<\/td>\n Looks modern, good for small operations<\/td>\n<\/tr>\n \n Async \/ throwing items<\/td>\n for try await \u2026, for await \u2026<\/td>\n Modern concurrency code<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n 8. Small Practice \u2013 Try these now<\/h3>\n
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