{"id":1289,"date":"2025-03-24T08:52:25","date_gmt":"2025-03-23T23:52:25","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1289"},"modified":"2025-03-24T08:52:25","modified_gmt":"2025-03-23T23:52:25","slug":"ruby%e3%81%aefor%e6%96%87%e3%81%a8%e4%bb%a3%e6%9b%bf%e6%89%8b%e6%b3%957%e9%81%b8%ef%bc%81%e7%8f%be%e5%a0%b4%e3%81%a7%e4%bd%bf%e3%81%88%e3%82%8b%e5%ae%9f%e8%b7%b5%e3%83%86%e3%82%af%e3%83%8b%e3%83%83","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1289","title":{"rendered":"Ruby\u306eFOR\u6587\u3068\u4ee3\u66ff\u624b\u6cd57\u9078\uff01\u73fe\u5834\u3067\u4f7f\u3048\u308b\u5b9f\u8df5\u30c6\u30af\u30cb\u30c3\u30af"},"content":{"rendered":"\n<div class=\"toc\"><br \/>\n<b>Warning<\/b>:  Undefined array key \"is_admin\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>116<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_category_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>121<\/b><br \/>\n<br \/>\n<b>Warning<\/b>:  Undefined array key \"is_top\" in <b>\/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/sango-theme\/library\/gutenberg\/dist\/classes\/Toc.php<\/b> on line <b>128<\/b><br \/>\n    <div id=\"toc_container\" class=\"sgb-toc--bullets js-smooth-scroll\" data-dialog-title=\"\u76ee\u6b21\">\n      <p class=\"toc_title\">\u76ee\u6b21 <\/p>\n      <ul class=\"toc_list\">  <li class=\"first\">    <a href=\"#i-0\">Ruby\u3067for\u6587\u3092\u4f7f\u3046\u57fa\u672c\u3068\u6ce8\u610f\u70b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">for\u6587\u306e\u57fa\u672c\u7684\u306a\u66f8\u304d\u65b9\u3068\u52d5\u4f5c\u539f\u7406<\/a>      <\/li>      <li>        <a href=\"#i-2\">\u4ed6\u8a00\u8a9e\u306efor\u6587\u3068\u306e\u91cd\u8981\u306a\u9055\u3044<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-3\">for\u6587\u4f7f\u7528\u6642\u306e\u4e00\u822c\u7684\u306a\u843d\u3068\u3057\u7a74<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-4\">\u73fe\u5834\u3067\u597d\u307e\u308c\u308bfor\u6587\u306e\u4ee3\u66ff\u624b\u6cd5<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-5\">each\u6587\u306b\u3088\u308b\u7c21\u6f54\u306a\u7e70\u308a\u8fd4\u3057\u51e6\u7406<\/a>      <\/li>      <li>        <a href=\"#i-6\">map\/collect\u3067\u914d\u5217\u3092\u52b9\u7387\u7684\u306b\u5909\u63db<\/a>      <\/li>      <li>        <a href=\"#i-7\">select\/reject\u3067\u30b9\u30de\u30fc\u30c8\u306b\u8981\u7d20\u3092\u62bd\u51fa<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-8\">times\u6587\u3067\u6307\u5b9a\u56de\u6570\u306e\u7e70\u308a\u8fd4\u3057\u3092\u5b9f\u73fe<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-9\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u610f\u8b58\u3057\u305f\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-10\">\u5404\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5\u306e\u5b9f\u884c\u901f\u5ea6\u6bd4\u8f03<\/a>      <\/li>      <li>        <a href=\"#i-11\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u6291\u3048\u308b\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-12\">\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u6700\u9069\u306a\u9078\u629e<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-13\">\u5b9f\u8df5\u7684\u306a\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9\u3068\u5b9f\u88c5\u4f8b<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-14\">\u30d5\u30a1\u30a4\u30eb\u51e6\u7406\u3067\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u65b9\u6cd5<\/a>      <\/li>      <li>        <a href=\"#i-15\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u51e6\u7406\u3067\u306e\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-16\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u51e6\u7406\u3067\u306e\u5b9f\u88c5\u4f8b<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-17\">\u30b3\u30fc\u30c9\u306e\u53ef\u8aad\u6027\u3092\u9ad8\u3081\u308b\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-18\">\u660e\u78ba\u306a\u610f\u56f3\u3092\u4f1d\u3048\u308b\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u9078\u629e<\/a>      <\/li>      <li>        <a href=\"#i-19\">\u30cd\u30b9\u30c8\u3092\u907f\u3051\u308b\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u624b\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-20\">\u30c6\u30b9\u30bf\u30d3\u30ea\u30c6\u30a3\u3092\u8003\u616e\u3057\u305f\u5b9f\u88c5\u65b9\u6cd5<\/a>      <\/li>    <\/ul>  <\/li><\/ul>\n      <a href=\"#\" class=\"sgb-toc-button js-toc-button\" rel=\"nofollow\" data-open-dialog=\"true\"><i class=\"fa fa-list\"><\/i><span class=\"sgb-toc-button__text\">\u76ee\u6b21\u3078<\/span><\/a>\n    <\/div><\/div><h2 class=\"wp-block-heading\" id=\"i-0\">Ruby\u3067for\u6587\u3092\u4f7f\u3046\u57fa\u672c\u3068\u6ce8\u610f\u70b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">for\u6587\u306e\u57fa\u672c\u7684\u306a\u66f8\u304d\u65b9\u3068\u52d5\u4f5c\u539f\u7406<\/h3>\n\n\n\n<p>Ruby\u306efor\u6587\u306f\u3001\u914d\u5217\u3084\u30cf\u30c3\u30b7\u30e5\u306a\u3069\u306e\u8981\u7d20\u3092\u9806\u756a\u306b\u51e6\u7406\u3059\u308b\u305f\u3081\u306e\u5236\u5fa1\u69cb\u9020\u3067\u3059\u3002\u57fa\u672c\u7684\u306a\u69cb\u6587\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">for \u5909\u6570 in \u7e70\u308a\u8fd4\u3057\u5bfe\u8c61\n  # \u51e6\u7406\u5185\u5bb9\nend<\/pre>\n\n\n\n<p>\u5177\u4f53\u7684\u306a\u4f7f\u7528\u4f8b\u3092\u898b\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u914d\u5217\u306e\u8981\u7d20\u3092\u9806\u756a\u306b\u51fa\u529b\nnumbers = [1, 2, 3, 4, 5]\nfor num in numbers\n  puts num\nend\n\n# \u7bc4\u56f2\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f7f\u7528\u3057\u305f\u7e70\u308a\u8fd4\u3057\nfor i in 1..5\n  puts \"\u30ab\u30a6\u30f3\u30c8: #{i}\"\nend\n\n# \u30cf\u30c3\u30b7\u30e5\u306e\u51e6\u7406\nuser = { name: \"\u7530\u4e2d\", age: 25, city: \"\u6771\u4eac\" }\nfor key, value in user\n  puts \"#{key}: #{value}\"\nend<\/pre>\n\n\n\n<p>\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\u3068\u3057\u3066\u3001Ruby\u306efor\u6587\u306f\u5185\u90e8\u7684\u306b\u306f<code>each<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3057\u3066\u5b9f\u88c5\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u305d\u306e\u305f\u3081\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u7279\u5fb4\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u3092\u4f5c\u6210\u3057\u306a\u3044\uff08\u5909\u6570\u304cfor\u6587\u306e\u5916\u3067\u3082\u53c2\u7167\u53ef\u80fd\uff09<\/li>\n\n\n\n<li>\u30a4\u30c6\u30ec\u30fc\u30bf\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u53d7\u3051\u53d6\u308b\u3053\u3068\u304c\u3067\u304d\u308b<\/li>\n\n\n\n<li><code>break<\/code>\u3001<code>next<\/code>\u3001<code>redo<\/code>\u306a\u3069\u306e\u5236\u5fa1\u304c\u53ef\u80fd<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-2\">\u4ed6\u8a00\u8a9e\u306efor\u6587\u3068\u306e\u91cd\u8981\u306a\u9055\u3044<\/h3>\n\n\n\n<p>Ruby\u306eFOR\u6587\u306f\u3001\u4ed6\u306e\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u8a00\u8a9e\u306e\u3082\u306e\u3068\u306f\u7570\u306a\u308b\u7279\u5fb4\u3092\u6301\u3063\u3066\u3044\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-40714f31-3f84-4d4b-92c6-9e4003e3aabd\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u8a00\u8a9e<\/th><th>for\u6587\u306e\u7279\u5fb4<\/th><th>\u30b9\u30b3\u30fc\u30d7<\/th><th>\u4e00\u822c\u7684\u306a\u4f7f\u7528\u983b\u5ea6<\/th><\/tr><\/thead><tbody><tr><td>Ruby<\/td><td>\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u30d9\u30fc\u30b9<\/td><td>\u5916\u90e8\u304b\u3089\u53c2\u7167\u53ef\u80fd<\/td><td>\u4f4e\u3044<\/td><\/tr><tr><td>Java<\/td><td>\u30ab\u30a6\u30f3\u30bf\u30d9\u30fc\u30b9<\/td><td>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u5185<\/td><td>\u9ad8\u3044<\/td><\/tr><tr><td>Python<\/td><td>\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u30d9\u30fc\u30b9<\/td><td>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u5185<\/td><td>\u9ad8\u3044<\/td><\/tr><tr><td>JavaScript<\/td><td>\u591a\u69d8\u306a\u5f62\u5f0f<\/td><td>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u5185<\/td><td>\u4e2d\u7a0b\u5ea6<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u7279\u306b\u6ce8\u76ee\u3059\u3079\u304d\u9055\u3044\u306f\u4ee5\u4e0b\u306e\u70b9\u3067\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># Ruby\u306e\u5834\u5408\uff1a\u5909\u6570\u30b9\u30b3\u30fc\u30d7\u306e\u4f8b\nfor i in 1..3\n  value = i\nend\nputs value  # =&gt; 3\uff08\u5916\u90e8\u304b\u3089\u30a2\u30af\u30bb\u30b9\u53ef\u80fd\uff09\n\n# \u4ed6\u8a00\u8a9e\u3067\u306e\u4e00\u822c\u7684\u306afor\u6587\uff08\u7591\u4f3c\u30b3\u30fc\u30c9\uff09\nfor (int i = 0; i &lt; 3; i++) {\n  int value = i;\n}\n\/\/ value \u306f\u672a\u5b9a\u7fa9\uff08\u30b9\u30b3\u30fc\u30d7\u5916\uff09<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-3\">for\u6587\u4f7f\u7528\u6642\u306e\u4e00\u822c\u7684\u306a\u843d\u3068\u3057\u7a74<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b9\u30b3\u30fc\u30d7\u306e\u8aa4\u89e3<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u610f\u56f3\u305b\u306c\u5909\u6570\u306e\u4e0a\u66f8\u304d\ntotal = 0\nfor total in 1..5\n  # total\u304c\u4e0a\u66f8\u304d\u3055\u308c\u308b\nend\nputs total  # =&gt; 5\uff08\u5143\u306e\u50240\u304c\u5931\u308f\u308c\u308b\uff09<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u554f\u984c<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u5927\u304d\u306a\u914d\u5217\u306b\u5bfe\u3059\u308b\u975e\u52b9\u7387\u306a\u51e6\u7406\nlarge_array = (1..1000000).to_a\nfor item in large_array\n  # \u5927\u91cf\u306e\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u5834\u5408\u3001\n  # each_slice\u7b49\u3092\u4f7f\u7528\u3057\u305f\u65b9\u304c\u52b9\u7387\u7684\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u4e26\u884c\u51e6\u7406\u3068\u306e\u76f8\u6027<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30b9\u30ec\u30c3\u30c9\u30bb\u30fc\u30d5\u3067\u306f\u306a\u3044\u51e6\u7406\nthreads = []\nshared_array = []\nfor i in 1..10\n  threads &lt;&lt; Thread.new {\n    shared_array &lt;&lt; i  # \u7af6\u5408\u306e\u53ef\u80fd\u6027\n  }\nend<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u843d\u3068\u3057\u7a74\u3092\u907f\u3051\u308b\u305f\u3081\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5909\u6570\u540d\u306e\u614e\u91cd\u306a\u9078\u629e<\/li>\n\n\n\n<li>\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u306e\u5834\u5408\u306f\u4ee3\u66ff\u624b\u6cd5\u306e\u691c\u8a0e<\/li>\n\n\n\n<li>\u4e26\u884c\u51e6\u7406\u304c\u5fc5\u8981\u306a\u5834\u5408\u306f\u9069\u5207\u306a\u540c\u671f\u6a5f\u69cb\u306e\u4f7f\u7528<\/li>\n\n\n\n<li>\u53ef\u80fd\u306a\u9650\u308a<code>each<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u4f7f\u7528\u3092\u691c\u8a0e<\/li>\n<\/ol>\n\n\n\n<p>Ruby\u306efor\u6587\u306f\u3001\u4ed6\u306e\u8a00\u8a9e\u304b\u3089\u79fb\u884c\u3057\u3066\u304d\u305f\u958b\u767a\u8005\u306b\u3068\u3063\u3066\u99b4\u67d3\u307f\u3084\u3059\u3044\u69cb\u6587\u3067\u3059\u304c\u3001Ruby\u306e\u601d\u60f3\u3084\u30a4\u30c7\u30a3\u30aa\u30e0\u306b\u5f93\u3046\u3068\u3001\u591a\u304f\u306e\u5834\u5408\u306f\u4ed6\u306e\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5\u3092\u9078\u629e\u3059\u308b\u3053\u3068\u304c\u63a8\u5968\u3055\u308c\u307e\u3059\u3002\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u3067\u306f\u3001\u305d\u308c\u3089\u306e\u4ee3\u66ff\u624b\u6cd5\u306b\u3064\u3044\u3066\u8a73\u3057\u304f\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-4\">\u73fe\u5834\u3067\u597d\u307e\u308c\u308bfor\u6587\u306e\u4ee3\u66ff\u624b\u6cd5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">each\u6587\u306b\u3088\u308b\u7c21\u6f54\u306a\u7e70\u308a\u8fd4\u3057\u51e6\u7406<\/h3>\n\n\n\n<p><code>each<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001Ruby\u3067\u6700\u3082\u4e00\u822c\u7684\u306b\u4f7f\u7528\u3055\u308c\u308b\u7e70\u308a\u8fd4\u3057\u51e6\u7406\u624b\u6cd5\u3067\u3059\u3002\u30b7\u30f3\u30d7\u30eb\u3067\u53ef\u8aad\u6027\u304c\u9ad8\u304f\u3001Ruby\u3089\u3057\u3044\u8a18\u8ff0\u304c\u53ef\u80fd\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u57fa\u672c\u7684\u306a\u4f7f\u7528\u65b9\u6cd5\n[1, 2, 3].each do |number|\n  puts number\nend\n\n# with_index\u3092\u4f7f\u7528\u3057\u305f\u4f8b\n['a', 'b', 'c'].each.with_index(1) do |letter, index|\n  puts \"#{index}: #{letter}\"  # \"1: a\", \"2: b\", \"3: c\"\nend\n\n# \u30cd\u30b9\u30c8\u3057\u305f\u914d\u5217\u306e\u51e6\u7406\nmatrix = [[1, 2], [3, 4]]\nmatrix.each do |row|\n  row.each do |element|\n    puts element\n  end\nend\n\n# \u30cf\u30c3\u30b7\u30e5\u306e\u51e6\u7406\nuser = { name: '\u5c71\u7530', age: 30 }\nuser.each do |key, value|\n  puts \"#{key}: #{value}\"\nend<\/pre>\n\n\n\n<p><code>each<\/code>\u3092\u4f7f\u7528\u3059\u308b\u4e3b\u306a\u30e1\u30ea\u30c3\u30c8\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u304c\u660e\u78ba<\/li>\n\n\n\n<li>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u304c\u53ef\u80fd<\/li>\n\n\n\n<li>\u8c4a\u5bcc\u306a\u95a2\u9023\u30e1\u30bd\u30c3\u30c9\uff08with_index, with_object\u7b49\uff09<\/li>\n\n\n\n<li>\u30a4\u30c7\u30a3\u30aa\u30de\u30c6\u30a3\u30c3\u30af\u306aRuby\u30b3\u30fc\u30c9<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-6\">map\/collect\u3067\u914d\u5217\u3092\u52b9\u7387\u7684\u306b\u5909\u63db<\/h3>\n\n\n\n<p><code>map<\/code>\uff08\u5225\u540d<code>collect<\/code>\uff09\u306f\u3001\u914d\u5217\u306e\u5404\u8981\u7d20\u3092\u5909\u63db\u3057\u3066\u65b0\u3057\u3044\u914d\u5217\u3092\u4f5c\u6210\u3059\u308b\u5834\u5408\u306b\u6700\u9069\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u6570\u5024\u306e\u914d\u5217\u30922\u500d\u306b\u3059\u308b\nnumbers = [1, 2, 3, 4, 5]\ndoubled = numbers.map { |n| n * 2 }\nputs doubled  # [2, 4, 6, 8, 10]\n\n# \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u7279\u5b9a\u306e\u5c5e\u6027\u3092\u62bd\u51fa\nusers = [\n  { name: '\u7530\u4e2d', age: 25 },\n  { name: '\u4f50\u85e4', age: 30 }\n]\nnames = users.map { |user| user[:name] }\nputs names  # ['\u7530\u4e2d', '\u4f50\u85e4']\n\n# \u6761\u4ef6\u4ed8\u304d\u5909\u63db\nnumbers = [1, 2, 3, 4, 5]\nresult = numbers.map do |n|\n  if n.even?\n    \"\u5076\u6570: #{n}\"\n  else\n    \"\u5947\u6570: #{n}\"\n  end\nend\nputs result  # [\"\u5947\u6570: 1\", \"\u5076\u6570: 2\", \"\u5947\u6570: 3\", \"\u5076\u6570: 4\", \"\u5947\u6570: 5\"]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">select\/reject\u3067\u30b9\u30de\u30fc\u30c8\u306b\u8981\u7d20\u3092\u62bd\u51fa<\/h3>\n\n\n\n<p><code>select<\/code>\uff08\u5225\u540d<code>find_all<\/code>\uff09\u3068<code>reject<\/code>\u306f\u3001\u6761\u4ef6\u306b\u57fa\u3065\u3044\u3066\u8981\u7d20\u3092\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u3059\u308b\u5834\u5408\u306b\u4f7f\u7528\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">numbers = [1, 2, 3, 4, 5, 6]\n\n# \u5076\u6570\u306e\u307f\u3092\u62bd\u51fa\nevens = numbers.select { |n| n.even? }\nputs evens  # [2, 4, 6]\n\n# \u5947\u6570\u3092\u9664\u5916\nnot_odds = numbers.reject { |n| n.odd? }\nputs not_odds  # [2, 4, 6]\n\n# \u8907\u96d1\u306a\u6761\u4ef6\u3067\u306e\u4f7f\u7528\u4f8b\nusers = [\n  { name: '\u7530\u4e2d', age: 25, active: true },\n  { name: '\u4f50\u85e4', age: 30, active: false },\n  { name: '\u9234\u6728', age: 22, active: true }\n]\n\nactive_young_users = users.select do |user|\n  user[:active] &amp;&amp; user[:age] &lt; 28\nend\n\nputs active_young_users\n# [{:name=&gt;\"\u7530\u4e2d\", :age=&gt;25, :active=&gt;true}, \n#  {:name=&gt;\"\u9234\u6728\", :age=&gt;22, :active=&gt;true}]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-8\">times\u6587\u3067\u6307\u5b9a\u56de\u6570\u306e\u7e70\u308a\u8fd4\u3057\u3092\u5b9f\u73fe<\/h3>\n\n\n\n<p><code>times<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u5358\u7d14\u306a\u56de\u6570\u6307\u5b9a\u306e\u7e70\u308a\u8fd4\u3057\u3092\u5b9f\u73fe\u3059\u308b\u5834\u5408\u306b\u6700\u9069\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u57fa\u672c\u7684\u306a\u4f7f\u7528\u65b9\u6cd5\n5.times { puts \"Hello\" }\n\n# \u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\n3.times do |i|\n  puts \"\u30ab\u30a6\u30f3\u30c8: #{i}\"  # 0\u304b\u3089\u59cb\u307e\u308b\nend\n\n# \u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u751f\u6210\nusers = []\n3.times do |i|\n  users &lt;&lt; { id: i + 1, name: \"\u30e6\u30fc\u30b6\u30fc#{i + 1}\" }\nend\n\n# \u521d\u671f\u5316\u51e6\u7406\u3067\u306e\u4f7f\u7528\u4f8b\nmatrix = []\n3.times do |i|\n  row = []\n  3.times do |j|\n    row &lt;&lt; i * 3 + j + 1\n  end\n  matrix &lt;&lt; row\nend\nputs matrix.inspect  # [[1, 2, 3], [4, 5, 6], [7, 8, 9]]<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u4ee3\u66ff\u624b\u6cd5\u306e\u4f7f\u3044\u5206\u3051\u30ac\u30a4\u30c9\u30e9\u30a4\u30f3\uff1a<\/p>\n\n\n<div id=\"id-00e96cb2-e8c1-4412-b373-c7214522dc52\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u30e1\u30bd\u30c3\u30c9<\/th><th>\u4e3b\u306a\u7528\u9014<\/th><th>\u7279\u5fb4<\/th><\/tr><\/thead><tbody><tr><td>each<\/td><td>\u8981\u7d20\u3054\u3068\u306e\u51e6\u7406<\/td><td>\u6700\u3082\u6c4e\u7528\u7684\u3001\u526f\u4f5c\u7528\u3092\u4f34\u3046\u51e6\u7406\u306b\u9069\u3059\u308b<\/td><\/tr><tr><td>map\/collect<\/td><td>\u8981\u7d20\u306e\u5909\u63db<\/td><td>\u65b0\u3057\u3044\u914d\u5217\u3092\u4f5c\u6210\u3001\u5909\u63db\u51e6\u7406\u306b\u6700\u9069<\/td><\/tr><tr><td>select\/reject<\/td><td>\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0<\/td><td>\u6761\u4ef6\u306b\u57fa\u3065\u304f\u8981\u7d20\u306e\u62bd\u51fa\u306b\u9069\u3059\u308b<\/td><\/tr><tr><td>times<\/td><td>\u56de\u6570\u6307\u5b9a\u306e\u7e70\u308a\u8fd4\u3057<\/td><td>\u30b7\u30f3\u30d7\u30eb\u306a\u7e70\u308a\u8fd4\u3057\u306b\u6700\u9069<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u3053\u308c\u3089\u306e\u4ee3\u66ff\u624b\u6cd5\u306f\u3001for\u6587\u3068\u6bd4\u8f03\u3057\u3066\u4ee5\u4e0b\u306e\u5229\u70b9\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u3088\u308a\u660e\u78ba\u306a\u610f\u56f3\u306e\u8868\u73fe<\/li>\n\n\n\n<li>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u306b\u3088\u308b\u67d4\u8edf\u306a\u51e6\u7406<\/li>\n\n\n\n<li>\u30d6\u30ed\u30c3\u30af\u30b9\u30b3\u30fc\u30d7\u306e\u9069\u5207\u306a\u7ba1\u7406<\/li>\n\n\n\n<li>\u95a2\u9023\u30e1\u30bd\u30c3\u30c9\u306b\u3088\u308b\u6a5f\u80fd\u62e1\u5f35<\/li>\n<\/ol>\n\n\n\n<p>\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u306f\u3001\u3053\u308c\u3089\u306e\u4ee3\u66ff\u624b\u6cd5\u3092\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u9069\u5207\u306b\u4f7f\u3044\u5206\u3051\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u4fdd\u5b88\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-9\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u610f\u8b58\u3057\u305f\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">\u5404\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5\u306e\u5b9f\u884c\u901f\u5ea6\u6bd4\u8f03<\/h3>\n\n\n\n<p>\u7570\u306a\u308b\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u624b\u6cd5\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6bd4\u8f03\u3059\u308b\u305f\u3081\u306b\u3001\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u30c6\u30b9\u30c8\u3092\u5b9f\u65bd\u3057\u3066\u307f\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'benchmark'\nrequire 'benchmark\/ips'\n\narray = (1..100000).to_a\n\nBenchmark.ips do |x|\n  x.report(\"for\") do\n    for i in array\n      i * 2\n    end\n  end\n\n  x.report(\"each\") do\n    array.each do |i|\n      i * 2\n    end\n  end\n\n  x.report(\"map\") do\n    array.map { |i| i * 2 }\n  end\n\n  x.report(\"times\") do\n    array.size.times do |i|\n      array[i] * 2\n    end\n  end\n\n  x.compare!\nend<\/pre>\n\n\n\n<p>\u5b9f\u884c\u7d50\u679c\u306e\u6bd4\u8f03\uff1a<\/p>\n\n\n<div id=\"id-4deabd7d-18b6-432c-9c7f-707c7a8be160\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u30e1\u30bd\u30c3\u30c9<\/th><th>\u76f8\u5bfe\u7684\u306a\u901f\u5ea6<\/th><th>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf<\/th><th>\u7528\u9014\u306b\u9069\u3057\u305f\u72b6\u6cc1<\/th><\/tr><\/thead><tbody><tr><td>each<\/td><td>1.0\uff08\u57fa\u6e96\uff09<\/td><td>\u4f4e<\/td><td>\u5358\u7d14\u306a\u7e70\u308a\u8fd4\u3057\u51e6\u7406<\/td><\/tr><tr><td>for<\/td><td>0.95<\/td><td>\u4e2d<\/td><td>\u5f8c\u65b9\u4e92\u63db\u6027\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><\/tr><tr><td>map<\/td><td>0.85<\/td><td>\u9ad8<\/td><td>\u65b0\u3057\u3044\u914d\u5217\u306e\u751f\u6210\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><\/tr><tr><td>times<\/td><td>1.2<\/td><td>\u4f4e<\/td><td>\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u30d9\u30fc\u30b9\u306e\u51e6\u7406<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u6291\u3048\u308b\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Enumerator\u306e\u6d3b\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30e1\u30e2\u30ea\u3092\u5927\u91cf\u306b\u6d88\u8cbb\u3059\u308b\u4f8b\nlarge_array = (1..1000000).to_a.map { |i| i * 2 }\n\n# \u30e1\u30e2\u30ea\u52b9\u7387\u306e\u826f\u3044\u5b9f\u88c5\nlarge_enum = (1..1000000).lazy.map { |i| i * 2 }\nlarge_enum.first(5)  # \u5fc5\u8981\u306a\u5206\u3060\u3051\u51e6\u7406\n\n# \u30d5\u30a1\u30a4\u30eb\u51e6\u7406\u3067\u306e\u4f8b\nFile.open('large_file.txt') do |file|\n  # \u4e00\u5ea6\u306b\u30d5\u30a1\u30a4\u30eb\u5168\u4f53\u3092\u8aad\u307f\u8fbc\u307e\u306a\u3044\n  file.each_line.lazy.map(&amp;:chomp).select { |line|\n    line.include?('important')\n  }.first(10)\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>each_slice\u306b\u3088\u308b\u5206\u5272\u51e6\u7406<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30e1\u30e2\u30ea\u3092\u52b9\u7387\u7684\u306b\u4f7f\u7528\u3059\u308b\u5206\u5272\u51e6\u7406\nlarge_array = (1..1000000).to_a\nlarge_array.each_slice(1000) do |slice|\n  # 1000\u4ef6\u305a\u3064\u51e6\u7406\n  slice.each do |item|\n    # \u51e6\u7406\u5185\u5bb9\n  end\nend\n\n# \u30d0\u30c3\u30c1\u51e6\u7406\u306e\u4f8b\nusers = User.all\nusers.each_slice(100) do |batch|\n  batch.each do |user|\n    # \u30e6\u30fc\u30b6\u30fc\u60c5\u5831\u306e\u66f4\u65b0\u51e6\u7406\n  end\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>find_each\u306e\u6d3b\u7528\uff08ActiveRecord\uff09<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30e1\u30e2\u30ea\u3092\u5927\u91cf\u306b\u6d88\u8cbb\u3059\u308b\u4f8b\nUser.all.each do |user|\n  # \u5168\u30ec\u30b3\u30fc\u30c9\u3092\u4e00\u5ea6\u306b\u30e1\u30e2\u30ea\u306b\u8aad\u307f\u8fbc\u3080\nend\n\n# \u30e1\u30e2\u30ea\u52b9\u7387\u306e\u826f\u3044\u5b9f\u88c5\nUser.find_each do |user|\n  # \u30d0\u30c3\u30c1\u30b5\u30a4\u30ba(\u30c7\u30d5\u30a9\u30eb\u30c81000)\u3054\u3068\u306b\u51e6\u7406\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-12\">\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u6700\u9069\u306a\u9078\u629e<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b9\u30c8\u30ea\u30fc\u30df\u30f3\u30b0\u51e6\u7406\u306e\u6d3b\u7528<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'csv'\n\n# \u30e1\u30e2\u30ea\u52b9\u7387\u306e\u826f\u3044CSV\u51e6\u7406\nCSV.foreach('large_file.csv') do |row|\n  # 1\u884c\u305a\u3064\u51e6\u7406\nend\n\n# \u4e26\u5217\u51e6\u7406\u3068\u306e\u7d44\u307f\u5408\u308f\u305b\nrequire 'parallel'\n\nParallel.each(CSV.foreach('large_file.csv'), in_processes: 4) do |row|\n  # \u4e26\u5217\u3067\u51e6\u7406\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u6700\u9069\u5316<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># N+1\u30af\u30a8\u30ea\u3092\u9632\u3050\n# \u60aa\u3044\u4f8b\nusers = User.all\nusers.each do |user|\n  puts user.posts.count  # \u5404\u30e6\u30fc\u30b6\u30fc\u3054\u3068\u306b\u30af\u30a8\u30ea\u304c\u767a\u884c\u3055\u308c\u308b\nend\n\n# \u826f\u3044\u4f8b\nusers = User.includes(:posts)\nusers.each do |user|\n  puts user.posts.size  # \u30d7\u30ea\u30ed\u30fc\u30c9\u6e08\u307f\u306e\u30c7\u30fc\u30bf\u3092\u4f7f\u7528\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u30e2\u30cb\u30bf\u30ea\u30f3\u30b0<\/strong><\/li>\n<\/ol>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u78ba\u8a8d\u3059\u308b\u30d8\u30eb\u30d1\u30fc\u30e1\u30bd\u30c3\u30c9\ndef memory_usage\n  `ps -o rss= -p #{Process.pid}`.to_i \/ 1024\nend\n\nbefore_mem = memory_usage\n# \u51e6\u7406\u5b9f\u884c\nafter_mem = memory_usage\nputs \"\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf: #{after_mem - before_mem}MB\"<\/pre>\n\n\n\n<p>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6700\u9069\u5316\u3059\u308b\u969b\u306e\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u51e6\u7406\u3059\u308b\u30c7\u30fc\u30bf\u91cf\u306b\u5fdc\u3058\u305f\u9069\u5207\u306a\u624b\u6cd5\u306e\u9078\u629e<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u30c8\u30ec\u30fc\u30c9\u30aa\u30d5\u3092\u8003\u616e<\/li>\n\n\n\n<li>\u5fc5\u8981\u306b\u5fdc\u3058\u305f\u4e26\u5217\u51e6\u7406\u306e\u6d3b\u7528<\/li>\n\n\n\n<li>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u306e\u6700\u9069\u5316<\/li>\n\n\n\n<li>\u5b9a\u671f\u7684\u306a\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30e2\u30cb\u30bf\u30ea\u30f3\u30b0<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u624b\u6cd5\u3092\u9069\u5207\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u5927\u898f\u6a21\u306a\u30c7\u30fc\u30bf\u51e6\u7406\u3067\u3082\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u6291\u3048\u3064\u3064\u3001\u52b9\u7387\u7684\u306a\u51e6\u7406\u3092\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-13\">\u5b9f\u8df5\u7684\u306a\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9\u3068\u5b9f\u88c5\u4f8b<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u30d5\u30a1\u30a4\u30eb\u51e6\u7406\u3067\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u30d5\u30a1\u30a4\u30eb\u51e6\u7406\u306f\u958b\u767a\u73fe\u5834\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9\u3067\u3059\u3002\u4ee5\u4e0b\u306b\u3001\u7570\u306a\u308b\u72b6\u6cc1\u3067\u306e\u6700\u9069\u306a\u5b9f\u88c5\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u5927\u5bb9\u91cf\u30ed\u30b0\u30d5\u30a1\u30a4\u30eb\u306e\u89e3\u6790\ndef analyze_log_file(file_path)\n  results = Hash.new(0)\n\n  File.open(file_path) do |file|\n    file.each_line.lazy\n        .map(&amp;:chomp)\n        .select { |line| line.match?(\/ERROR|WARN\/) }\n        .each_slice(1000) do |lines|\n      lines.each do |line|\n        error_type = line[\/(ERROR|WARN)\/]\n        results[error_type] += 1\n      end\n    end\n  end\n\n  results\nend\n\n# CSV\u30d5\u30a1\u30a4\u30eb\u306e\u5909\u63db\u51e6\u7406\nrequire 'csv'\n\ndef transform_csv(input_path, output_path)\n  CSV.open(output_path, 'wb') do |csv_out|\n    CSV.foreach(input_path, headers: true) do |row|\n      # \u30c7\u30fc\u30bf\u5909\u63db\u51e6\u7406\n      transformed_row = {\n        'id' =&gt; row['id'],\n        'full_name' =&gt; \"#{row['first_name']} #{row['last_name']}\",\n        'age' =&gt; calculate_age(row['birth_date'])\n      }\n      csv_out &lt;&lt; transformed_row.values\n    end\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u51e6\u7406\u3067\u306e\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>ActiveRecord\u3092\u4f7f\u7528\u3057\u305f\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u51e6\u7406\u3067\u306e\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u4f8b\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">class UserDataProcessor\n  def self.update_user_statistics\n    # \u30d0\u30c3\u30c1\u51e6\u7406\u306b\u3088\u308b\u52b9\u7387\u7684\u306a\u66f4\u65b0\n    User.find_each(batch_size: 500) do |user|\n      stats = calculate_user_stats(user)\n      user.update(\n        total_posts: stats[:posts],\n        average_likes: stats[:avg_likes]\n      )\n    end\n  end\n\n  def self.bulk_import_users(user_data)\n    # \u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u3068\u30d0\u30eb\u30af\u30a4\u30f3\u30b5\u30fc\u30c8\u306e\u6d3b\u7528\n    User.transaction do\n      user_data.each_slice(100) do |batch|\n        User.import batch, validate: true\n      end\n    end\n  end\n\n  private\n\n  def self.calculate_user_stats(user)\n    {\n      posts: user.posts.count,\n      avg_likes: user.posts.average(:likes_count)\n    }\n  end\nend\n\n# \u95a2\u9023\u30c7\u30fc\u30bf\u306e\u52b9\u7387\u7684\u306a\u53d6\u5f97\nclass PostsController &lt; ApplicationController\n  def index\n    @posts = Post.includes(:user, :comments)\n                 .where(status: 'published')\n                 .order(created_at: :desc)\n                 .page(params[:page])\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-16\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u51e6\u7406\u3067\u306e\u5b9f\u88c5\u4f8b<\/h3>\n\n\n\n<p>\u5916\u90e8API\u3068\u306e\u9023\u643a\u6642\u306e\u52b9\u7387\u7684\u306a\u30c7\u30fc\u30bf\u51e6\u7406\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">require 'net\/http'\nrequire 'json'\n\nclass ApiDataProcessor\n  def self.process_paginated_api_data(base_url)\n    page = 1\n    results = []\n\n    loop do\n      response = fetch_api_page(base_url, page)\n      break if response.empty?\n\n      # \u30ec\u30b9\u30dd\u30f3\u30b9\u30c7\u30fc\u30bf\u306e\u51e6\u7406\n      process_response_data(response) do |item|\n        results &lt;&lt; transform_item(item)\n      end\n\n      page += 1\n    end\n\n    results\n  end\n\n  private\n\n  def self.fetch_api_page(base_url, page)\n    uri = URI(\"#{base_url}?page=#{page}\")\n    response = Net::HTTP.get(uri)\n    JSON.parse(response)\n  rescue JSON::ParserError, Net::HTTPError =&gt; e\n    logger.error \"API\u53d6\u5f97\u30a8\u30e9\u30fc: #{e.message}\"\n    []\n  end\n\n  def self.process_response_data(data)\n    data.each_slice(50) do |batch|\n      batch.each do |item|\n        yield(item) if block_given?\n      end\n    end\n  end\n\n  def self.transform_item(item)\n    {\n      id: item['id'],\n      title: item['title'].strip,\n      processed_at: Time.current\n    }\n  end\nend\n\n# \u4f7f\u7528\u4f8b\ndata = ApiDataProcessor.process_paginated_api_data('https:\/\/api.example.com\/items')<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u88c5\u4f8b\u306b\u5171\u901a\u3059\u308b\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u306e\u9069\u5207\u306a\u5b9f\u88c5<\/li>\n\n\n\n<li>\u30d0\u30c3\u30c1\u51e6\u7406\u306b\u3088\u308b\u52b9\u7387\u5316<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u6700\u9069\u5316<\/li>\n\n\n\n<li>\u30c8\u30e9\u30f3\u30b6\u30af\u30b7\u30e7\u30f3\u7ba1\u7406<\/li>\n\n\n\n<li>\u30ed\u30b0\u8a18\u9332\u306b\u3088\u308b\u51e6\u7406\u306e\u53ef\u8996\u5316<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d1\u30bf\u30fc\u30f3\u306f\u3001\u5b9f\u969b\u306e\u958b\u767a\u73fe\u5834\u3067\u983b\u7e41\u306b\u4f7f\u7528\u3055\u308c\u308b\u5b9f\u88c5\u65b9\u6cd5\u3067\u3042\u308a\u3001\u30b3\u30fc\u30c9\u306e\u54c1\u8cea\u3068\u4fdd\u5b88\u6027\u3092\u9ad8\u3081\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-17\">\u30b3\u30fc\u30c9\u306e\u53ef\u8aad\u6027\u3092\u9ad8\u3081\u308b\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u660e\u78ba\u306a\u610f\u56f3\u3092\u4f1d\u3048\u308b\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u9078\u629e<\/h3>\n\n\n\n<p>\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u629e\u306f\u3001\u30b3\u30fc\u30c9\u306e\u610f\u56f3\u3092\u660e\u78ba\u306b\u4f1d\u3048\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u60aa\u3044\u4f8b\uff1a\u610f\u56f3\u304c\u4e0d\u660e\u78ba\ndef process_users(users)\n  result = []\n  for user in users\n    if user.age &gt;= 20\n      result &lt;&lt; user\n    end\n  end\n  result\nend\n\n# \u826f\u3044\u4f8b\uff1a\u610f\u56f3\u304c\u660e\u78ba\ndef process_users(users)\n  users.select { |user| user.age &gt;= 20 }\nend\n\n# \u3055\u3089\u306b\u826f\u3044\u4f8b\uff1a\u30d3\u30b8\u30cd\u30b9\u30ed\u30b8\u30c3\u30af\u3092\u660e\u78ba\u306b\u8868\u73fe\ndef find_adult_users(users)\n  users.select(&amp;:adult?)\nend\n\nclass User\n  def adult?\n    age &gt;= 20\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-19\">\u30cd\u30b9\u30c8\u3092\u907f\u3051\u308b\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u624b\u6cd5<\/h3>\n\n\n\n<p>\u6df1\u3044\u30cd\u30b9\u30c8\u306f\u53ef\u8aad\u6027\u3092\u640d\u306d\u308b\u4e3b\u306a\u8981\u56e0\u3067\u3059\u3002\u4ee5\u4e0b\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3067\u30cd\u30b9\u30c8\u3092\u6e1b\u3089\u3059\u3053\u3068\u304c\u3067\u304d\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u60aa\u3044\u4f8b\uff1a\u6df1\u3044\u30cd\u30b9\u30c8\ndef process_data(items)\n  results = []\n  items.each do |item|\n    if item.valid?\n      if item.status == 'active'\n        if item.price &gt; 1000\n          results &lt;&lt; {\n            id: item.id,\n            name: item.name,\n            price: item.price\n          }\n        end\n      end\n    end\n  end\n  results\nend\n\n# \u826f\u3044\u4f8b\uff1a\u65e9\u671f\u30ea\u30bf\u30fc\u30f3\u3068\u30e1\u30bd\u30c3\u30c9\u62bd\u51fa\ndef process_data(items)\n  items.select(&amp;:valid?)\n       .select { |item| item.status == 'active' }\n       .select { |item| item.price &gt; 1000 }\n       .map { |item| format_item(item) }\nend\n\nprivate\n\ndef format_item(item)\n  {\n    id: item.id,\n    name: item.name,\n    price: item.price\n  }\nend\n\n# \u8907\u96d1\u306a\u6761\u4ef6\u3092\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u30ab\u30d7\u30bb\u30eb\u5316\nclass ItemProcessor\n  def initialize(item)\n    @item = item\n  end\n\n  def processable?\n    valid? &amp;&amp; active? &amp;&amp; expensive?\n  end\n\n  private\n\n  def valid?\n    @item.valid?\n  end\n\n  def active?\n    @item.status == 'active'\n  end\n\n  def expensive?\n    @item.price &gt; 1000\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-20\">\u30c6\u30b9\u30bf\u30d3\u30ea\u30c6\u30a3\u3092\u8003\u616e\u3057\u305f\u5b9f\u88c5\u65b9\u6cd5<\/h3>\n\n\n\n<p>\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u306e\u30c6\u30b9\u30c8\u3092\u5bb9\u6613\u306b\u3059\u308b\u5b9f\u88c5\u65b9\u6cd5\u3092\u793a\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\"># \u30c6\u30b9\u30bf\u30d6\u30eb\u306a\u30af\u30e9\u30b9\u8a2d\u8a08\nclass OrderProcessor\n  def initialize(orders, logger = nil)\n    @orders = orders\n    @logger = logger || default_logger\n  end\n\n  def process_orders\n    @orders.each_with_object([]) do |order, processed|\n      result = process_single_order(order)\n      processed &lt;&lt; result if result\n    end\n  end\n\n  private\n\n  def process_single_order(order)\n    validate_order(order)\n    calculate_total(order)\n  rescue StandardError =&gt; e\n    log_error(e, order)\n    nil\n  end\n\n  def validate_order(order)\n    raise InvalidOrderError unless order.valid?\n  end\n\n  def calculate_total(order)\n    OrderCalculator.new(order).calculate\n  end\n\n  def log_error(error, order)\n    @logger.error(\"\u6ce8\u6587\u51e6\u7406\u30a8\u30e9\u30fc: #{error.message}, \u6ce8\u6587ID: #{order.id}\")\n  end\n\n  def default_logger\n    Logger.new(STDOUT)\n  end\nend\n\n# \u30c6\u30b9\u30c8\u30b3\u30fc\u30c9\u4f8b\nRSpec.describe OrderProcessor do\n  let(:logger) { instance_double('Logger') }\n  let(:orders) { [build(:order)] }\n\n  subject { described_class.new(orders, logger) }\n\n  describe '#process_orders' do\n    context '\u6b63\u5e38\u306a\u6ce8\u6587\u306e\u5834\u5408' do\n      it '\u6ce8\u6587\u304c\u6b63\u3057\u304f\u51e6\u7406\u3055\u308c\u308b' do\n        expect(subject.process_orders).not_to be_empty\n      end\n    end\n\n    context '\u30a8\u30e9\u30fc\u304c\u767a\u751f\u3057\u305f\u5834\u5408' do\n      before do\n        allow(logger).to receive(:error)\n      end\n\n      it '\u30a8\u30e9\u30fc\u304c\u30ed\u30b0\u306b\u8a18\u9332\u3055\u308c\u308b' do\n        expect(logger).to receive(:error).with(\/\u6ce8\u6587\u51e6\u7406\u30a8\u30e9\u30fc\/)\n        subject.process_orders\n      end\n    end\n  end\nend<\/pre>\n\n\n\n<p>\u53ef\u8aad\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u305f\u3081\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u306e\u610f\u56f3\u3092\u660e\u78ba\u306b\u8868\u73fe\u3059\u308b\u9069\u5207\u306a\u30e1\u30bd\u30c3\u30c9\u3092\u9078\u629e<\/li>\n\n\n\n<li>\u8907\u96d1\u306a\u6761\u4ef6\u306f\u30d7\u30e9\u30a4\u30d9\u30fc\u30c8\u30e1\u30bd\u30c3\u30c9\u307e\u305f\u306f\u5c02\u7528\u30af\u30e9\u30b9\u306b\u62bd\u51fa<\/li>\n\n\n\n<li>\u65e9\u671f\u30ea\u30bf\u30fc\u30f3\u3092\u6d3b\u7528\u3057\u3066\u30cd\u30b9\u30c8\u3092\u6e1b\u3089\u3059<\/li>\n\n\n\n<li>\u610f\u5473\u306e\u3042\u308b\u5909\u6570\u540d\u3068\u30e1\u30bd\u30c3\u30c9\u540d\u3092\u4f7f\u7528<\/li>\n\n\n\n<li>\u5358\u4e00\u8cac\u4efb\u306e\u539f\u5247\u306b\u5f93\u3063\u3066\u30af\u30e9\u30b9\u3092\u8a2d\u8a08<\/li>\n\n\n\n<li>\u30c6\u30b9\u30c8\u3057\u3084\u3059\u3044\u4f9d\u5b58\u6027\u306e\u6ce8\u5165\u3092\u8003\u616e<\/li>\n\n\n\n<li>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0\u3092\u9069\u5207\u306b\u5b9f\u88c5<\/li>\n\n\n\n<li>\u30ed\u30b0\u51fa\u529b\u306b\u3088\u308b\u51e6\u7406\u306e\u53ef\u8996\u5316<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u610f\u8b58\u3059\u308b\u3053\u3068\u3067\u3001\u4fdd\u5b88\u6027\u304c\u9ad8\u304f\u3001\u30c1\u30fc\u30e0\u958b\u767a\u306b\u9069\u3057\u305f\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Warning: Undefined array key &#8220;is_admin&#8221; in \/home\/xs392991\/dexall.co.jp\/public_html\/articles\/wp-content\/themes\/ &#8230; <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":{"0":"post-1289","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-ruby","7":"nothumb"},"_links":{"self":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1289","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1289"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1289\/revisions"}],"predecessor-version":[{"id":1292,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1289\/revisions\/1292"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1289"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1289"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1289"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}