{"id":1276,"date":"2025-03-24T08:52:26","date_gmt":"2025-03-23T23:52:26","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1276"},"modified":"2025-03-24T08:52:26","modified_gmt":"2025-03-23T23:52:26","slug":"%e3%80%90%e4%bf%9d%e5%ad%98%e7%89%88%e3%80%91ruby-enum%e3%81%ae%e5%ae%8c%e5%85%a8%e3%82%ac%e3%82%a4%e3%83%89%ef%bc%9a20%e5%80%8b%e3%81%ae%e5%ae%9f%e8%b7%b5%e7%9a%84%e3%81%aa%e4%bd%bf%e7%94%a8%e4%be%8b","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1276","title":{"rendered":"\u3010\u4fdd\u5b58\u7248\u3011Ruby Enum\u306e\u5b8c\u5168\u30ac\u30a4\u30c9\uff1a20\u500b\u306e\u5b9f\u8df5\u7684\u306a\u4f7f\u7528\u4f8b\u3068\u6700\u9069\u5316\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\">Enum\u3068\u306f\uff1f\u521d\u5fc3\u8005\u3067\u3082\u308f\u304b\u308bRuby\u306e\u57fa\u790e\u6982\u5ff5<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">Enum\u306fRuby\u3067\u914d\u5217\u51e6\u7406\u3092\u7c21\u5358\u306b\u3059\u308b\u9b54\u6cd5\u306e\u3088\u3046\u306a\u6a5f\u80fd<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-3\">\u4ed6\u8a00\u8a9e\u306e\u30a4\u30c6\u30ec\u30fc\u30bf\u3068\u306e\u9055\u3044\u304b\u3089\u7406\u89e3\u3059\u308bEnum<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-4\">Enum\u306e\u57fa\u672c\u30e1\u30bd\u30c3\u30c9\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-5\">map\/collect\u3067\u914d\u5217\u3092\u81ea\u7531\u306b\u5909\u63db\u3059\u308b<\/a>      <\/li>      <li>        <a href=\"#i-6\">select\/reject\u6761\u4ef6\u306b\u5408\u3046\u8981\u7d20\u3092\u62bd\u51fa\u3059\u308b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-7\">reduce\/inject\u3067\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3092\u96c6\u8a08\u3059\u308b<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-8\">\u77e5\u3063\u3066\u5f97\u3059\u308b\uff01\u5b9f\u8df5\u7684\u306aEnum\u306e\u6d3b\u7528\u30d1\u30bf\u30fc\u30f3<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-9\">\u8907\u6570\u306eEnum\u30e1\u30bd\u30c3\u30c9\u3092\u7d44\u307f\u5408\u308f\u305b\u3066\u51e6\u7406\u3092\u52b9\u7387\u5316\u3059\u308b<\/a>      <\/li>      <li>        <a href=\"#i-10\">\u30d6\u30ed\u30c3\u30af\u3068Enum\u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u9ad8\u5ea6\u306a\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-11\">\u5b9f\u52d9\u3067\u3088\u304f\u4f7f\u3046Enum\u306e\u30a4\u30c7\u30a3\u30aa\u30e0\u96c6<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-12\">Enum\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u30ac\u30a4\u30c9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-13\">each vs map\uff1a\u9069\u5207\u306a\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u629e<\/a>      <\/li>      <li>        <a href=\"#i-14\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u91cd\u8996\u3057\u305fEnum\u306e\u4f7f\u3044\u65b9<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-15\">\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-16\">\u3088\u304f\u3042\u308b\u9593\u9055\u3044\u3068\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-17\">\u521d\u5fc3\u8005\u304c\u306a\u308a\u3084\u3059\u3044Enum\u306e\u843d\u3068\u3057\u7a74<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-18\">\u30c7\u30d0\u30c3\u30b0\u306b\u4f7f\u3048\u308bEnum\u306e\u30c1\u30a7\u30c3\u30af\u30dd\u30a4\u30f3\u30c8<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-19\">Enum\u3092\u4f7f\u3063\u305f\u5b9f\u88c5\u4f8b\uff1a\u73fe\u5834\u3067\u4f7f\u3048\u308b\u30b3\u30fc\u30c9\u30ec\u30b7\u30d4\u96c6<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-20\">\u30c7\u30fc\u30bf\u4e00\u62ec\u51e6\u7406\u3092Enum\u3067\u30a8\u30ec\u30ac\u30f3\u30c8\u306b\u66f8\u304f<\/a>      <\/li>      <li>        <a href=\"#i-21\">\u8907\u96d1\u306a\u691c\u7d22\u30ed\u30b8\u30c3\u30af\u3092Enum\u3067\u6574\u7406\u3059\u308b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-22\">\u30d0\u30c3\u30c1\u51e6\u7406\u3067\u306eEnum\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/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\">Enum\u3068\u306f\uff1f\u521d\u5fc3\u8005\u3067\u3082\u308f\u304b\u308bRuby\u306e\u57fa\u790e\u6982\u5ff5<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">Enum\u306fRuby\u3067\u914d\u5217\u51e6\u7406\u3092\u7c21\u5358\u306b\u3059\u308b\u9b54\u6cd5\u306e\u3088\u3046\u306a\u6a5f\u80fd<\/h3>\n\n\n\n<p>Ruby\u306e<code>Enumerable<\/code>\u30e2\u30b8\u30e5\u30fc\u30eb\u306f\u3001\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\uff08\u914d\u5217\u3084\u30cf\u30c3\u30b7\u30e5\u306a\u3069\uff09\u3092\u6271\u3046\u305f\u3081\u306e\u5f37\u529b\u306a\u30e1\u30bd\u30c3\u30c9\u7fa4\u3092\u63d0\u4f9b\u3057\u307e\u3059\u3002\u3053\u306e\u30e2\u30b8\u30e5\u30fc\u30eb\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u306f\u3001Ruby\u3067\u306e\u52b9\u7387\u7684\u306a\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u306e\u9375\u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"i-2\">Enumerable \u30e2\u30b8\u30e5\u30fc\u30eb\u306e\u7279\u5fb4<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7e70\u308a\u8fd4\u3057\u51e6\u7406\u306e\u62bd\u8c61\u5316<\/strong>: \u914d\u5217\u3084\u30cf\u30c3\u30b7\u30e5\u306a\u3069\u306e\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u306b\u5bfe\u3059\u308b\u7e70\u308a\u8fd4\u3057\u51e6\u7406\u3092\u3001\u30b7\u30f3\u30d7\u30eb\u3067\u8aad\u307f\u3084\u3059\u3044\u5f62\u3067\u66f8\u3051\u307e\u3059<\/li>\n\n\n\n<li><strong>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u306e\u5b9f\u73fe<\/strong>: \u8907\u6570\u306e\u51e6\u7406\u3092\u9023\u7d50\u3057\u3066\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u3001\u30c7\u30fc\u30bf\u306e\u52a0\u5de5\u3092\u6bb5\u968e\u7684\u306b\u884c\u3048\u307e\u3059<\/li>\n\n\n\n<li><strong>\u9045\u5ef6\u8a55\u4fa1<\/strong>: \u5fc5\u8981\u306b\u306a\u308b\u307e\u3067\u5b9f\u969b\u306e\u51e6\u7406\u3092\u9045\u3089\u305b\u308b\u3053\u3068\u304c\u3067\u304d\u3001\u30e1\u30e2\u30ea\u52b9\u7387\u304c\u826f\u3044<\/li>\n<\/ul>\n\n\n\n<p>\u4ee5\u4e0b\u306f\u57fa\u672c\u7684\u306a\u4f7f\u7528\u4f8b\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=\"\"># \u914d\u5217\u306e\u5404\u8981\u7d20\u30922\u500d\u306b\u3059\u308b\nnumbers = [1, 2, 3, 4, 5]\ndoubled = numbers.map { |n| n * 2 }\n# =&gt; [2, 4, 6, 8, 10]\n\n# \u5076\u6570\u306e\u307f\u3092\u62bd\u51fa\u3059\u308b\nevens = numbers.select { |n| n.even? }\n# =&gt; [2, 4]\n\n# \u8981\u7d20\u306e\u5408\u8a08\u3092\u8a08\u7b97\u3059\u308b\nsum = numbers.reduce(0) { |acc, n| acc + n }\n# =&gt; 15<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-3\">\u4ed6\u8a00\u8a9e\u306e\u30a4\u30c6\u30ec\u30fc\u30bf\u3068\u306e\u9055\u3044\u304b\u3089\u7406\u89e3\u3059\u308bEnum<\/h3>\n\n\n\n<p>Ruby\u306e<code>Enumerable<\/code>\u306f\u3001\u4ed6\u306e\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u8a00\u8a9e\u306e\u30a4\u30c6\u30ec\u30fc\u30bf\u3068\u6bd4\u8f03\u3057\u3066\u3001\u3044\u304f\u3064\u304b\u306e\u7279\u5fb4\u7684\u306a\u9055\u3044\u304c\u3042\u308a\u307e\u3059\uff1a<\/p>\n\n\n<div id=\"id-3e87a36d-c4b4-45cc-9ce4-f21e78e1c9de\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u7279\u5fb4<\/th><th>Ruby\uff08Enumerable\uff09<\/th><th>\u4ed6\u8a00\u8a9e\u306e\u4e00\u822c\u7684\u306a\u30a4\u30c6\u30ec\u30fc\u30bf<\/th><\/tr><\/thead><tbody><tr><td>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3<\/td><td>\u81ea\u7136\u306a\u5f62\u3067\u8a18\u8ff0\u53ef\u80fd<\/td><td>\u8a00\u8a9e\u306b\u3088\u3063\u3066\u306f\u8907\u96d1\u306a\u69cb\u6587\u304c\u5fc5\u8981<\/td><\/tr><tr><td>\u30d6\u30ed\u30c3\u30af\u69cb\u6587<\/td><td>\u8aad\u307f\u3084\u3059\u3044<code>{ }<\/code> \u3084 <code>do...end<\/code><\/td><td>\u591a\u304f\u306e\u5834\u5408\u3001\u30e9\u30e0\u30c0\u5f0f\u3084\u7121\u540d\u95a2\u6570\u3092\u4f7f\u7528<\/td><\/tr><tr><td>\u9045\u5ef6\u8a55\u4fa1<\/td><td><code>lazy<\/code> \u3092\u4f7f\u7528\u3057\u3066\u5b9f\u73fe\u53ef\u80fd<\/td><td>\u8a00\u8a9e\u306b\u3088\u3063\u3066\u7570\u306a\u308b\u5b9f\u88c5\u304c\u5fc5\u8981<\/td><\/tr><tr><td>\u30e1\u30bd\u30c3\u30c9\u306e\u8c4a\u5bcc\u3055<\/td><td>50\u4ee5\u4e0a\u306e\u7d44\u307f\u8fbc\u307f\u30e1\u30bd\u30c3\u30c9<\/td><td>\u57fa\u672c\u7684\u306a\u64cd\u4f5c\u306e\u307f\u3092\u63d0\u4f9b\u3059\u308b\u3053\u3068\u304c\u591a\u3044<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<p>\u5177\u4f53\u7684\u306a\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=\"\"># Ruby\u3067\u306e\u5b9f\u88c5\nresult = [1, 2, 3, 4, 5]\n  .map { |n| n * 2 }     # \u5404\u8981\u7d20\u30922\u500d\n  .select { |n| n &gt; 5 }  # 5\u3088\u308a\u5927\u304d\u3044\u8981\u7d20\u3092\u9078\u629e\n  .reduce(0, :+)         # \u5408\u8a08\u3092\u8a08\u7b97\n# =&gt; 24\n\n# \u540c\u69d8\u306e\u51e6\u7406\u3092\u5f93\u6765\u306e\u30eb\u30fc\u30d7\u3067\u66f8\u3044\u305f\u5834\u5408\nnumbers = [1, 2, 3, 4, 5]\ndoubled = []\nnumbers.each { |n| doubled &lt;&lt; n * 2 }  # 2\u500d\u306b\u3059\u308b\nfiltered = []\ndoubled.each { |n| filtered &lt;&lt; n if n &gt; 5 }  # \u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\nsum = 0\nfiltered.each { |n| sum += n }  # \u5408\u8a08\u3092\u8a08\u7b97\n# =&gt; 24<\/pre>\n\n\n\n<p>\u3053\u306e\u3088\u3046\u306b\u3001Enum\u3092\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30b3\u30fc\u30c9\u304c\u3088\u308a<strong>\u5ba3\u8a00\u7684<\/strong>\u306b\u306a\u308a\u3001\u300c\u4f55\u3092\u3059\u308b\u304b\u300d\u304c\u660e\u78ba<\/li>\n\n\n\n<li><strong>\u4e00\u6642\u5909\u6570<\/strong>\u304c\u6e1b\u308a\u3001\u30b3\u30fc\u30c9\u304c\u30af\u30ea\u30fc\u30f3\u306b<\/li>\n\n\n\n<li><strong>\u30d0\u30b0\u306e\u53ef\u80fd\u6027<\/strong>\u304c\u6e1b\u5c11<\/li>\n\n\n\n<li><strong>\u53ef\u8aad\u6027<\/strong>\u304c\u5927\u5e45\u306b\u5411\u4e0a<\/li>\n<\/ol>\n\n\n\n<p>\u4ee5\u4e0a\u304cEnum\u306e\u57fa\u672c\u7684\u306a\u6982\u5ff5\u3067\u3059\u3002\u3053\u308c\u3089\u306e\u57fa\u790e\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u8907\u96d1\u306a\u51e6\u7406\u3082\u52b9\u7387\u7684\u306b\u5b9f\u88c5\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-4\">Enum\u306e\u57fa\u672c\u30e1\u30bd\u30c3\u30c9\u5b8c\u5168\u30de\u30b9\u30bf\u30fc<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">map\/collect\u3067\u914d\u5217\u3092\u81ea\u7531\u306b\u5909\u63db\u3059\u308b<\/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\u6700\u3082\u57fa\u672c\u7684\u306aEnum\u30e1\u30bd\u30c3\u30c9\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\u3044\u65b9\nnumbers = [1, 2, 3, 4, 5]\nsquared = numbers.map { |n| n ** 2 }\n# =&gt; [1, 4, 9, 16, 25]\n\n# \u8907\u6570\u306e\u6761\u4ef6\u3067\u306e\u5909\u63db\nusers = [\n  { name: \"Alice\", age: 25 },\n  { name: \"Bob\", age: 30 }\n]\nnames = users.map { |user| user[:name] }\n# =&gt; [\"Alice\", \"Bob\"]\n\n# \u30e1\u30bd\u30c3\u30c9\u53c2\u7167\u3092\u4f7f\u7528\u3057\u305f\u7c21\u6f54\u306a\u8a18\u6cd5\nwords = [\"hello\", \"world\"]\nupper_words = words.map(&amp;:upcase)\n# =&gt; [\"HELLO\", \"WORLD\"]<\/pre>\n\n\n\n<p>\u5b9f\u8df5\u7684\u306a\u30e6\u30fc\u30b9\u30b1\u30fc\u30b9\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=\"\"># API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6574\u5f62\napi_response = [\n  { \"user_id\" =&gt; 1, \"data\" =&gt; { \"name\" =&gt; \"Alice\" }},\n  { \"user_id\" =&gt; 2, \"data\" =&gt; { \"name\" =&gt; \"Bob\" }}\n]\nformatted = api_response.map { |r| \n  {\n    id: r[\"user_id\"],\n    name: r[\"data\"][\"name\"]\n  }\n}\n# =&gt; [{:id=&gt;1, :name=&gt;\"Alice\"}, {:id=&gt;2, :name=&gt;\"Bob\"}]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-6\">select\/reject\u6761\u4ef6\u306b\u5408\u3046\u8981\u7d20\u3092\u62bd\u51fa\u3059\u308b<\/h3>\n\n\n\n<p><code>select<\/code>\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\u30e1\u30bd\u30c3\u30c9\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=\"\">numbers = [1, 2, 3, 4, 5, 6]\n\n# select\u306f\u6761\u4ef6\u306b\u5408\u3046\u8981\u7d20\u3092\u62bd\u51fa\nevens = numbers.select { |n| n.even? }\n# =&gt; [2, 4, 6]\n\n# reject\u306f\u6761\u4ef6\u306b\u5408\u3046\u8981\u7d20\u3092\u9664\u5916\nnon_evens = numbers.reject { |n| n.even? }\n# =&gt; [1, 3, 5]\n\n# \u8907\u96d1\u306a\u6761\u4ef6\u3067\u306e\u4f7f\u7528\u4f8b\nusers = [\n  { name: \"Alice\", age: 25, active: true },\n  { name: \"Bob\", age: 30, active: false },\n  { name: \"Charlie\", age: 20, active: true }\n]\n\nactive_adult_users = users.select { |user| \n  user[:age] &gt;= 20 &amp;&amp; user[:active]\n}\n# =&gt; [{:name=&gt;\"Alice\", :age=&gt;25, :active=&gt;true}]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">reduce\/inject\u3067\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u3092\u96c6\u8a08\u3059\u308b<\/h3>\n\n\n\n<p><code>reduce<\/code>\uff08\u5225\u540d<code>inject<\/code>\uff09\u306f\u3001\u914d\u5217\u306e\u8981\u7d20\u3092\u96c6\u8a08\u3057\u3066\u5358\u4e00\u306e\u5024\u3092\u5f97\u308b\u30e1\u30bd\u30c3\u30c9\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=\"\">numbers = [1, 2, 3, 4, 5]\n\n# \u57fa\u672c\u7684\u306a\u5408\u8a08\u8a08\u7b97\nsum = numbers.reduce(0) { |acc, n| acc + n }\n# =&gt; 15\n\n# \u521d\u671f\u5024\u3092\u7701\u7565\u3057\u305f\u5834\u5408\uff08\u6700\u521d\u306e\u8981\u7d20\u304c\u521d\u671f\u5024\u306b\u306a\u308b\uff09\nproduct = numbers.reduce(:*)\n# =&gt; 120\n\n# \u3088\u308a\u8907\u96d1\u306a\u96c6\u8a08\u306e\u4f8b\nwords = [\"ruby\", \"is\", \"awesome\"]\nword_lengths = words.reduce({}) { |hash, word|\n  hash[word] = word.length\n  hash\n}\n# =&gt; {\"ruby\"=&gt;4, \"is\"=&gt;2, \"awesome\"=&gt;7}<\/pre>\n\n\n\n<p>\u5b9f\u8df5\u7684\u306a\u4f7f\u7528\u4f8b\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=\"\"># \u58f2\u4e0a\u30c7\u30fc\u30bf\u306e\u96c6\u8a08\nsales = [\n  { product: \"A\", amount: 100 },\n  { product: \"B\", amount: 200 },\n  { product: \"A\", amount: 150 }\n]\n\nsales_by_product = sales.reduce(Hash.new(0)) { |hash, sale|\n  hash[sale[:product]] += sale[:amount]\n  hash\n}\n# =&gt; {\"A\"=&gt;250, \"B\"=&gt;200}<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u57fa\u672c\u30e1\u30bd\u30c3\u30c9\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u8907\u96d1\u306a\u51e6\u7406\u3082\u7c21\u6f54\u306b\u66f8\u304f\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=\"\"># \u5546\u54c1\u30c7\u30fc\u30bf\u304b\u3089\u30011000\u5186\u4ee5\u4e0a\u306e\u5546\u54c1\u306e\u7a0e\u8fbc\u4fa1\u683c\u3092\u8a08\u7b97\u3059\u308b\nproducts = [\n  { name: \"\u5546\u54c1A\", price: 800 },\n  { name: \"\u5546\u54c1B\", price: 1200 },\n  { name: \"\u5546\u54c1C\", price: 1500 }\n]\n\nexpensive_products_with_tax = products\n  .select { |p| p[:price] &gt;= 1000 }  # 1000\u5186\u4ee5\u4e0a\u3092\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\n  .map { |p| \n    {\n      name: p[:name],\n      price_with_tax: (p[:price] * 1.1).round\n    }\n  }\n# =&gt; [{:name=&gt;\"\u5546\u54c1B\", :price_with_tax=&gt;1320}, \n#     {:name=&gt;\"\u5546\u54c1C\", :price_with_tax=&gt;1650}]<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30e1\u30bd\u30c3\u30c9\u306f\u3001Ruby\u3067\u306e\u914d\u5217\u51e6\u7406\u306e\u57fa\u790e\u3068\u306a\u308b\u91cd\u8981\u306a\u8981\u7d20\u3067\u3059\u3002\u9069\u5207\u306b\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u30b3\u30fc\u30c9\u306e\u53ef\u8aad\u6027\u3068\u4fdd\u5b88\u6027\u3092\u5927\u304d\u304f\u5411\u4e0a\u3055\u305b\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-8\">\u77e5\u3063\u3066\u5f97\u3059\u308b\uff01\u5b9f\u8df5\u7684\u306aEnum\u306e\u6d3b\u7528\u30d1\u30bf\u30fc\u30f3<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-9\">\u8907\u6570\u306eEnum\u30e1\u30bd\u30c3\u30c9\u3092\u7d44\u307f\u5408\u308f\u305b\u3066\u51e6\u7406\u3092\u52b9\u7387\u5316\u3059\u308b<\/h3>\n\n\n\n<p>\u5b9f\u8df5\u7684\u306a\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u3067\u306f\u3001\u8907\u6570\u306eEnum\u30e1\u30bd\u30c3\u30c9\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u8907\u96d1\u306a\u51e6\u7406\u3092\u7c21\u6f54\u306b\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\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=\"\"># \u30e6\u30fc\u30b6\u30fc\u30c7\u30fc\u30bf\u304b\u3089\u6761\u4ef6\u306b\u5408\u3046\u60c5\u5831\u3092\u62bd\u51fa\u3057\u3066\u52a0\u5de5\u3059\u308b\nusers = [\n  { id: 1, name: \"Alice\", age: 25, points: 100 },\n  { id: 2, name: \"Bob\", age: 30, points: 150 },\n  { id: 3, name: \"Charlie\", age: 20, points: 80 }\n]\n\n# 25\u6b73\u4ee5\u4e0a\u306e\u30e6\u30fc\u30b6\u30fc\u306e\u30dd\u30a4\u30f3\u30c8\u309220%\u30a2\u30c3\u30d7\u3057\u3066\u3001\u540d\u524d\u3068\u30dd\u30a4\u30f3\u30c8\u306e\u914d\u5217\u3092\u4f5c\u6210\nresult = users\n  .select { |user| user[:age] &gt;= 25 }  # 25\u6b73\u4ee5\u4e0a\u3092\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\n  .map { |user| \n    {\n      name: user[:name],\n      updated_points: (user[:points] * 1.2).round\n    }\n  }\n# =&gt; [{:name=&gt;\"Alice\", :updated_points=&gt;120}, \n#     {:name=&gt;\"Bob\", :updated_points=&gt;180}]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-10\">\u30d6\u30ed\u30c3\u30af\u3068Enum\u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u9ad8\u5ea6\u306a\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>\u30d6\u30ed\u30c3\u30af\u3068Enum\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u67d4\u8edf\u306a\u51e6\u7406\u304c\u53ef\u80fd\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=\"\"># \u30ab\u30b9\u30bf\u30e0\u30bd\u30fc\u30c8\u6761\u4ef6\u3092\u5b9f\u88c5\u3059\u308b\nclass Product\n  attr_reader :name, :price, :stock\n\n  def initialize(name, price, stock)\n    @name = name\n    @price = price\n    @stock = stock\n  end\nend\n\nproducts = [\n  Product.new(\"A\", 1000, 5),\n  Product.new(\"B\", 800, 2),\n  Product.new(\"C\", 1200, 8)\n]\n\n# \u5728\u5eab\u304c3\u500b\u4ee5\u4e0a\u3042\u308b\u5546\u54c1\u3092\u4fa1\u683c\u306e\u5b89\u3044\u9806\u306b\u30bd\u30fc\u30c8\nsorted_products = products\n  .select { |p| p.stock &gt;= 3 }\n  .sort_by { |p| p.price }\n  .map { |p| \"#{p.name}: #{p.price}\u5186 (\u5728\u5eab: #{p.stock}\u500b)\" }\n# =&gt; [\"A: 1000\u5186 (\u5728\u5eab: 5\u500b)\", \"C: 1200\u5186 (\u5728\u5eab: 8\u500b)\"]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">\u5b9f\u52d9\u3067\u3088\u304f\u4f7f\u3046Enum\u306e\u30a4\u30c7\u30a3\u30aa\u30e0\u96c6<\/h3>\n\n\n\n<p>\u5b9f\u52d9\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u51e6\u7406\u30d1\u30bf\u30fc\u30f3\u3092Enum\u3067\u52b9\u7387\u7684\u306b\u5b9f\u88c5\u3059\u308b\u65b9\u6cd5\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30b0\u30eb\u30fc\u30d7\u5316\u3068\u96c6\u8a08\u306e\u7d44\u307f\u5408\u308f\u305b<\/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=\"\"># \u6ce8\u6587\u30c7\u30fc\u30bf\u3092\u6708\u3054\u3068\u306b\u96c6\u8a08\u3059\u308b\norders = [\n  { date: \"2024-01-15\", amount: 1000 },\n  { date: \"2024-01-20\", amount: 2000 },\n  { date: \"2024-02-10\", amount: 1500 }\n]\n\nmonthly_totals = orders.group_by { |order| \n  Date.parse(order[:date]).strftime(\"%Y-%m\")\n}.transform_values { |orders| \n  orders.sum { |order| order[:amount] }\n}\n# =&gt; {\"2024-01\"=&gt;3000, \"2024-02\"=&gt;1500}<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u6761\u4ef6\u4ed8\u304d\u30de\u30c3\u30d4\u30f3\u30b0<\/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\u30c6\u30fc\u30bf\u30b9\u306b\u5fdc\u3058\u3066\u7570\u306a\u308b\u51e6\u7406\u3092\u9069\u7528\u3059\u308b\ntasks = [\n  { id: 1, status: \"pending\", name: \"Task 1\" },\n  { id: 2, status: \"completed\", name: \"Task 2\" },\n  { id: 3, status: \"pending\", name: \"Task 3\" }\n]\n\nprocessed_tasks = tasks.map { |task|\n  case task[:status]\n  when \"pending\"\n    { id: task[:id], message: \"\u8981\u5bfe\u5fdc: #{task[:name]}\" }\n  when \"completed\"\n    { id: task[:id], message: \"\u5b8c\u4e86\u6e08: #{task[:name]}\" }\n  end\n}\n# =&gt; [{:id=&gt;1, :message=&gt;\"\u8981\u5bfe\u5fdc: Task 1\"},\n#     {:id=&gt;2, :message=&gt;\"\u5b8c\u4e86\u6e08: Task 2\"},\n#     {:id=&gt;3, :message=&gt;\"\u8981\u5bfe\u5fdc: Task 3\"}]<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li>\u968e\u5c64\u5316\u3055\u308c\u305f\u30c7\u30fc\u30bf\u306e\u51e6\u7406<\/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=\"\"># \u968e\u5c64\u69cb\u9020\u306e\u30c7\u30fc\u30bf\u3092\u5e73\u5766\u5316\u3057\u3066\u51e6\u7406\u3059\u308b\ndepartments = [\n  {\n    name: \"\u55b6\u696d\u90e8\",\n    teams: [\n      { name: \"\u56fd\u5185\u55b6\u696d\", members: 5 },\n      { name: \"\u6d77\u5916\u55b6\u696d\", members: 3 }\n    ]\n  },\n  {\n    name: \"\u958b\u767a\u90e8\",\n    teams: [\n      { name: \"\u30d5\u30ed\u30f3\u30c8\u30a8\u30f3\u30c9\", members: 4 },\n      { name: \"\u30d0\u30c3\u30af\u30a8\u30f3\u30c9\", members: 6 }\n    ]\n  }\n]\n\n# \u90e8\u7f72\u3054\u3068\u306e\u7dcf\u30e1\u30f3\u30d0\u30fc\u6570\u3092\u8a08\u7b97\ndepartment_members = departments.map { |dept|\n  {\n    department: dept[:name],\n    total_members: dept[:teams].sum { |team| team[:members] }\n  }\n}\n# =&gt; [{:department=&gt;\"\u55b6\u696d\u90e8\", :total_members=&gt;8},\n#     {:department=&gt;\"\u958b\u767a\u90e8\", :total_members=&gt;10}]<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d1\u30bf\u30fc\u30f3\u3092\u7406\u89e3\u3057\u3001\u9069\u5207\u306b\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u8907\u96d1\u306a\u696d\u52d9\u8981\u4ef6\u3082\u52b9\u7387\u7684\u306b\u5b9f\u88c5\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-12\">Enum\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u30ac\u30a4\u30c9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-13\">each vs map\uff1a\u9069\u5207\u306a\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u629e<\/h3>\n\n\n\n<p>Enum\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u629e\u306f\u3001\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306b\u5927\u304d\u306a\u5f71\u97ff\u3092\u4e0e\u3048\u307e\u3059\u3002\u4ee5\u4e0b\u304c\u4e3b\u8981\u306a\u30e1\u30bd\u30c3\u30c9\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u7279\u6027\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=\"\"># \u60aa\u3044\u4f8b\uff1a\u65b0\u3057\u3044\u914d\u5217\u304c\u5fc5\u8981\u306a\u3044\u306e\u306bmap\u3092\u4f7f\u7528\nnumbers = (1..1000000).to_a\n\n# \u30e1\u30e2\u30ea\u52b9\u7387\u304c\u60aa\u3044\u5b9f\u88c5\nnumbers.map { |n| puts n if n.even? }  # \u4e0d\u8981\u306a\u914d\u5217\u3092\u4f5c\u6210\n\n# \u826f\u3044\u4f8b\uff1a\u526f\u4f5c\u7528\u306e\u307f\u306e\u51e6\u7406\u306b\u306feach\u3092\u4f7f\u7528\nnumbers.each { |n| puts n if n.even? }  # \u30e1\u30e2\u30ea\u52b9\u7387\u304c\u826f\u3044<\/pre>\n\n\n\n<p>\u30e1\u30bd\u30c3\u30c9\u9078\u629e\u306e\u30ac\u30a4\u30c9\u30e9\u30a4\u30f3\uff1a<\/p>\n\n\n<div id=\"id-fdbab201-dd61-4ca5-80f1-bd908816c37d\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u30e1\u30bd\u30c3\u30c9<\/th><th>\u4f7f\u7528\u3059\u3079\u304d\u5834\u5408<\/th><th>\u907f\u3051\u308b\u3079\u304d\u5834\u5408<\/th><\/tr><\/thead><tbody><tr><td>each<\/td><td>\u526f\u4f5c\u7528\u304c\u76ee\u7684\u306e\u51e6\u7406<\/td><td>\u65b0\u3057\u3044\u30b3\u30ec\u30af\u30b7\u30e7\u30f3\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><\/tr><tr><td>map<\/td><td>\u5909\u63db\u5f8c\u306e\u914d\u5217\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><td>\u7d50\u679c\u3092\u4f7f\u7528\u3057\u306a\u3044\u5834\u5408<\/td><\/tr><tr><td>select\/reject<\/td><td>\u6761\u4ef6\u3067\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u3059\u308b\u5834\u5408<\/td><td>\u5168\u4ef6\u5fc5\u8981\u306a\u5834\u5408<\/td><\/tr><tr><td>reduce<\/td><td>\u96c6\u8a08\u51e6\u7406\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><td>\u4e2d\u9593\u7d50\u679c\u304c\u5fc5\u8981\u306a\u5834\u5408<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u91cd\u8996\u3057\u305fEnum\u306e\u4f7f\u3044\u65b9<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u306a\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u6700\u9069\u5316\u3059\u308b\u65b9\u6cd5\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=\"\"># \u30e1\u30e2\u30ea\u52b9\u7387\u306e\u60aa\u3044\u5b9f\u88c5\ndef process_large_data(numbers)\n  # \u4e2d\u9593\u914d\u5217\u3092\u305f\u304f\u3055\u3093\u751f\u6210\n  result = numbers\n    .map { |n| n * 2 }\n    .select { |n| n &gt; 1000 }\n    .map { |n| n.to_s }\n  result\nend\n\n# \u30e1\u30e2\u30ea\u52b9\u7387\u306e\u826f\u3044\u5b9f\u88c5\ndef process_large_data_optimized(numbers)\n  # \u4e00\u5ea6\u306e\u8d70\u67fb\u3067\u51e6\u7406\u3092\u5b8c\u7d50\n  numbers.each_with_object([]) do |n, result|\n    doubled = n * 2\n    result &lt;&lt; doubled.to_s if doubled &gt; 1000\n  end\nend\n\n# lazy\u3092\u4f7f\u7528\u3057\u305f\u5b9f\u88c5\ndef process_large_data_lazy(numbers)\n  numbers\n    .lazy\n    .map { |n| n * 2 }\n    .select { |n| n &gt; 1000 }\n    .map { |n| n.to_s }\n    .force\nend<\/pre>\n\n\n\n<p><code>lazy<\/code>\u8a55\u4fa1\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u6ce8\u610f\u70b9\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5c0f\u3055\u306a\u30c7\u30fc\u30bf\u30bb\u30c3\u30c8\u3067\u306f\u901a\u5e38\u306e\u5b9f\u88c5\u306e\u65b9\u304c\u9ad8\u901f<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3068\u51e6\u7406\u901f\u5ea6\u306f\u30c8\u30ec\u30fc\u30c9\u30aa\u30d5<\/li>\n\n\n\n<li>\u7121\u9650\u30b7\u30fc\u30b1\u30f3\u30b9\u306e\u51e6\u7406\u306b\u7279\u306b\u6709\u52b9<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u3092\u52b9\u7387\u7684\u306b\u51e6\u7406\u3059\u308b\u305f\u3081\u306e\u30c6\u30af\u30cb\u30c3\u30af\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30d0\u30c3\u30c1\u51e6\u7406\u306e\u6d3b\u7528<\/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\u52b9\u7387\u306e\u826f\u3044\u30d0\u30c3\u30c1\u51e6\u7406\ndef process_in_batches(items, batch_size = 1000)\n  items.each_slice(batch_size).map do |batch|\n    batch.map { |item| process_item(item) }\n  end.flatten\nend\n\ndef process_item(item)\n  # \u91cd\u3044\u51e6\u7406\n  sleep(0.001)\n  item * 2\nend\n\n# \u4f7f\u7528\u4f8b\nlarge_array = (1..10000).to_a\nresult = process_in_batches(large_array)<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u65e9\u671f\u30ea\u30bf\u30fc\u30f3\u306e\u6d3b\u7528<\/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=\"\"># \u6761\u4ef6\u3092\u6e80\u305f\u3059\u6700\u521d\u306e\u8981\u7d20\u3092\u898b\u3064\u3051\u308b\uff08\u52b9\u7387\u7684\uff09\ndef find_first_match(items)\n  items.each do |item|\n    return item if meets_criteria?(item)\n  end\n  nil\nend\n\n# \u975e\u52b9\u7387\u306a\u5b9f\u88c5\uff08\u5168\u4ef6\u51e6\u7406\u3059\u308b\uff09\ndef find_first_match_inefficient(items)\n  items.select { |item| meets_criteria?(item) }.first\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li>\u30d9\u30f3\u30c1\u30de\u30fc\u30af\u3092\u6d3b\u7528\u3057\u305f\u6700\u9069\u5316<\/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 'benchmark'\n\ndef benchmark_operations\n  array = (1..100000).to_a\n\n  Benchmark.bm do |x|\n    x.report(\"map + select:\") { \n      array.map { |n| n * 2 }.select { |n| n &gt; 1000 }\n    }\n\n    x.report(\"each_with_object:\") {\n      array.each_with_object([]) { |n, result|\n        doubled = n * 2\n        result &lt;&lt; doubled if doubled &gt; 1000\n      }\n    }\n\n    x.report(\"lazy evaluation:\") {\n      array.lazy.map { |n| n * 2 }.select { |n| n &gt; 1000 }.force\n    }\n  end\nend<\/pre>\n\n\n\n<p>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6700\u9069\u5316\u306e\u30c1\u30a7\u30c3\u30af\u30ea\u30b9\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u30b5\u30a4\u30ba\u306e\u78ba\u8a8d<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5c0f\u898f\u6a21\uff08\u6570\u5343\u4ef6\u4ee5\u4e0b\uff09\uff1a\u901a\u5e38\u306e\u5b9f\u88c5\u3067\u5341\u5206<\/li>\n\n\n\n<li>\u4e2d\u898f\u6a21\uff08\u6570\u4e07\u4ef6\uff09\uff1a\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306b\u6ce8\u610f<\/li>\n\n\n\n<li>\u5927\u898f\u6a21\uff08\u6570\u5341\u4e07\u4ef6\u4ee5\u4e0a\uff09\uff1a\u30d0\u30c3\u30c1\u51e6\u7406\u3084lazy\u8a55\u4fa1\u3092\u691c\u8a0e<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u76e3\u8996<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>GC.stat \u3092\u4f7f\u7528\u3057\u3066\u30e1\u30e2\u30ea\u4f7f\u7528\u72b6\u6cc1\u3092\u78ba\u8a8d<\/li>\n\n\n\n<li>\u5fc5\u8981\u306b\u5fdc\u3058\u3066\u30d7\u30ed\u30d5\u30a1\u30a4\u30ea\u30f3\u30b0\u30c4\u30fc\u30eb\u3092\u4f7f\u7528<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u51e6\u7406\u306e\u7279\u6027\u306b\u5fdc\u3058\u305f\u6700\u9069\u5316<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5168\u4ef6\u51e6\u7406\u304c\u5fc5\u8981\u306a\u5834\u5408\uff1a\u30d0\u30c3\u30c1\u51e6\u7406\u3092\u691c\u8a0e<\/li>\n\n\n\n<li>\u6761\u4ef6\u306b\u5408\u3046\u8981\u7d20\u306e\u307f\u5fc5\u8981\uff1a\u65e9\u671f\u30ea\u30bf\u30fc\u30f3\u3092\u6d3b\u7528<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u5236\u7d04\u304c\u53b3\u3057\u3044\uff1alazy\u8a55\u4fa1\u3092\u4f7f\u7528<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6700\u9069\u5316\u30c6\u30af\u30cb\u30c3\u30af\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\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u7dad\u6301\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-16\">\u3088\u304f\u3042\u308b\u9593\u9055\u3044\u3068\u30c8\u30e9\u30d6\u30eb\u30b7\u30e5\u30fc\u30c6\u30a3\u30f3\u30b0<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-17\">\u521d\u5fc3\u8005\u304c\u306a\u308a\u3084\u3059\u3044Enum\u306e\u843d\u3068\u3057\u7a74<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\u3068\u975e\u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\u306e\u6df7\u540c<\/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=\"\"># \u826f\u304f\u3042\u308b\u9593\u9055\u3044\nnumbers = [1, 2, 3, 4, 5]\nnumbers.select! { |n| n.even? }  # \u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\nputs numbers.length  # =&gt; 2\uff08\u5143\u306e\u914d\u5217\u304c\u5909\u66f4\u3055\u308c\u3066\u3044\u308b\uff09\n\n# \u63a8\u5968\u3055\u308c\u308b\u65b9\u6cd5\nnumbers = [1, 2, 3, 4, 5]\neven_numbers = numbers.select { |n| n.even? }  # \u65b0\u3057\u3044\u914d\u5217\u3092\u4f5c\u6210\nputs numbers.length  # =&gt; 5\uff08\u5143\u306e\u914d\u5217\u306f\u5909\u66f4\u3055\u308c\u3066\u3044\u306a\u3044\uff09\nputs even_numbers.length  # =&gt; 2<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30d6\u30ed\u30c3\u30af\u306e\u623b\u308a\u5024\u3092\u610f\u8b58\u3057\u3066\u3044\u306a\u3044<\/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\u3057\u306a\u3044\u7d50\u679c\u306b\u306a\u308b\u4f8b\nusers = [\n  { name: \"Alice\", age: 25 },\n  { name: \"Bob\", age: 30 }\n]\n\n# \u9593\u9055\u3063\u305f\u5b9f\u88c5\nresult = users.map do |user|\n  if user[:age] &gt; 25\n    user[:name].upcase\n  end\nend\n# =&gt; [\"Alice\", nil]  # \u6761\u4ef6\u306b\u5408\u308f\u306a\u3044\u5834\u5408\u306bnil\u304c\u8fd4\u308b\n\n# \u6b63\u3057\u3044\u5b9f\u88c5\nresult = users.map do |user|\n  user[:age] &gt; 25 ? user[:name].upcase : user[:name]\nend\n# =&gt; [\"Alice\", \"BOB\"]<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u306e\u9806\u5e8f\u306b\u3088\u308b\u975e\u52b9\u7387<\/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=\"\">numbers = (1..1000).to_a\n\n# \u975e\u52b9\u7387\u306a\u5b9f\u88c5\nresult = numbers\n  .map { |n| n * 2 }     # 1000\u500b\u306e\u8981\u7d20\u3092\u51e6\u7406\n  .select { |n| n &lt; 100 } # \u4e0d\u8981\u306a\u8981\u7d20\u3082\u5909\u63db\u3057\u3066\u3044\u308b\n\n# \u52b9\u7387\u7684\u306a\u5b9f\u88c5\nresult = numbers\n  .select { |n| n &lt; 50 }  # \u5148\u306b\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\n  .map { |n| n * 2 }      # \u5fc5\u8981\u306a\u8981\u7d20\u306e\u307f\u5909\u63db<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u30c7\u30d0\u30c3\u30b0\u306b\u4f7f\u3048\u308bEnum\u306e\u30c1\u30a7\u30c3\u30af\u30dd\u30a4\u30f3\u30c8<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u4e2d\u9593\u7d50\u679c\u306e\u78ba\u8a8d<\/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=\"\"># \u30c7\u30d0\u30c3\u30b0\u7528\u306etap\u30e1\u30bd\u30c3\u30c9\u3092\u6d3b\u7528\nresult = (1..5).to_a\n  .map { |n| n * 2 }\n  .tap { |arr| puts \"After map: #{arr.inspect}\" }\n  .select { |n| n &gt; 5 }\n  .tap { |arr| puts \"After select: #{arr.inspect}\" }\n  .reduce(0, :+)\n  .tap { |sum| puts \"Final sum: #{sum}\" }\n\n# \u51fa\u529b:\n# After map: [2, 4, 6, 8, 10]\n# After select: [6, 8, 10]\n# Final sum: 24<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><strong>\u30a8\u30e9\u30fc\u306e\u7279\u5b9a\u3068\u5bfe\u51e6<\/strong><\/li>\n<\/ol>\n\n\n\n<p>\u3088\u304f\u3042\u308b\u30a8\u30e9\u30fc\u3068\u305d\u306e\u5bfe\u51e6\u6cd5\uff1a<\/p>\n\n\n<div id=\"id-5c0b4666-78a8-4241-87cb-88e39fc8cb33\">\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u30a8\u30e9\u30fc<\/th><th>\u539f\u56e0<\/th><th>\u5bfe\u51e6\u6cd5<\/th><\/tr><\/thead><tbody><tr><td>NoMethodError<\/td><td>nil\u306b\u5bfe\u3059\u308b\u30e1\u30bd\u30c3\u30c9\u547c\u3073\u51fa\u3057<\/td><td>\u5b58\u5728\u30c1\u30a7\u30c3\u30af\u3092\u8ffd\u52a0<\/td><\/tr><tr><td>undefined method `each\u2019<\/td><td>Enumerable\u3067\u306a\u3044\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u4f7f\u7528<\/td><td>\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u578b\u3092\u78ba\u8a8d<\/td><\/tr><tr><td>ArgumentError<\/td><td>\u30d6\u30ed\u30c3\u30af\u30d1\u30e9\u30e1\u30fc\u30bf\u306e\u6570\u304c\u4e0d\u6b63<\/td><td>\u30e1\u30bd\u30c3\u30c9\u306e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u78ba\u8a8d<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div>\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=\"\"># \u30a8\u30e9\u30fc\u767a\u751f\u4f8b\u3068\u305d\u306e\u5bfe\u51e6\nusers = [\n  { name: \"Alice\", email: \"alice@example.com\" },\n  { name: \"Bob\", email: nil },\n  { name: \"Charlie\", email: \"charlie@example.com\" }\n]\n\n# \u30a8\u30e9\u30fc\u304c\u767a\u751f\u3059\u308b\u5b9f\u88c5\nbegin \n  users.map { |user| user[:email].upcase }\nrescue =&gt; e\n  puts \"\u30a8\u30e9\u30fc\u767a\u751f: #{e.message}\"\nend\n\n# \u5b89\u5168\u306a\u5b9f\u88c5\nusers.map { |user| user[:email]&amp;.upcase || \"NO EMAIL\" }<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u554f\u984c\u306e\u30c7\u30d0\u30c3\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=\"\">require 'benchmark'\n\ndef debug_performance\n  array = (1..10000).to_a\n\n  Benchmark.bm do |x|\n    x.report(\"Original:\") do\n      array\n        .map { |n| n * 2 }\n        .select { |n| n &gt; 1000 }\n        .map { |n| n.to_s }\n    end\n\n    x.report(\"Optimized:\") do\n      array.each_with_object([]) do |n, result|\n        doubled = n * 2\n        result &lt;&lt; doubled.to_s if doubled &gt; 1000\n      end\n    end\n  end\nend\n\n# \u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u30c7\u30d0\u30c3\u30b0\ndef monitor_memory\n  before = GC.stat[:heap_allocated_objects]\n  yield\n  after = GC.stat[:heap_allocated_objects]\n  puts \"Objects allocated: #{after - before}\"\nend\n\n# \u4f7f\u7528\u4f8b\nmonitor_memory do\n  result = (1..10000).to_a.map { |n| n * 2 }\nend<\/pre>\n\n\n\n<p>\u30c7\u30d0\u30c3\u30b0\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u6bb5\u968e\u7684\u306a\u691c\u8a3c<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5404\u51e6\u7406\u30b9\u30c6\u30c3\u30d7\u306e\u7d50\u679c\u3092\u78ba\u8a8d<\/li>\n\n\n\n<li>\u671f\u5f85\u3059\u308b\u578b\u3084\u5024\u306e\u691c\u8a3c<\/li>\n\n\n\n<li>\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9\u306e\u30c6\u30b9\u30c8<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u51e6\u7406\u306e\u5b9f\u88c5<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9069\u5207\u306a\u4f8b\u5916\u51e6\u7406\u306e\u8ffd\u52a0<\/li>\n\n\n\n<li>nil\u30c1\u30a7\u30c3\u30af\u306e\u5b9f\u88c5<\/li>\n\n\n\n<li>\u30c7\u30d5\u30a9\u30eb\u30c8\u5024\u306e\u8a2d\u5b9a<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30e2\u30cb\u30bf\u30ea\u30f3\u30b0<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u51e6\u7406\u6642\u9593\u306e\u8a08\u6e2c<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u76e3\u8996<\/li>\n\n\n\n<li>\u30dc\u30c8\u30eb\u30cd\u30c3\u30af\u306e\u7279\u5b9a<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u6ce8\u610f\u70b9\u3068\u30c7\u30d0\u30c3\u30b0\u30c6\u30af\u30cb\u30c3\u30af\u3092\u610f\u8b58\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u4fe1\u983c\u6027\u306e\u9ad8\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-19\">Enum\u3092\u4f7f\u3063\u305f\u5b9f\u88c5\u4f8b\uff1a\u73fe\u5834\u3067\u4f7f\u3048\u308b\u30b3\u30fc\u30c9\u30ec\u30b7\u30d4\u96c6<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-20\">\u30c7\u30fc\u30bf\u4e00\u62ec\u51e6\u7406\u3092Enum\u3067\u30a8\u30ec\u30ac\u30f3\u30c8\u306b\u66f8\u304f<\/h3>\n\n\n\n<p>\u5b9f\u52d9\u3067\u3088\u304f\u906d\u9047\u3059\u308b\u4e00\u62ec\u51e6\u7406\u306e\u30b7\u30ca\u30ea\u30aa\u3068\u3001Enum\u3092\u4f7f\u3063\u305f\u52b9\u7387\u7684\u306a\u5b9f\u88c5\u65b9\u6cd5\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>CSV\u30c7\u30fc\u30bf\u306e\u4e00\u62ec\u51e6\u7406<\/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\nclass UserDataProcessor\n  def self.process_csv(file_path)\n    CSV.read(file_path, headers: true)\n      .map { |row| row.to_h }\n      .each_with_object({valid: [], invalid: []}) do |user, result|\n        if valid_user?(user)\n          result[:valid] &lt;&lt; normalize_user(user)\n        else\n          result[:invalid] &lt;&lt; {\n            data: user,\n            errors: validate_user(user)\n          }\n        end\n      end\n  end\n\n  private\n\n  def self.valid_user?(user)\n    user['email'].to_s.include?('@') &amp;&amp;\n      user['age'].to_i.positive? &amp;&amp;\n      user['name'].to_s.length &gt;= 2\n  end\n\n  def self.normalize_user(user)\n    {\n      name: user['name'].strip.capitalize,\n      email: user['email'].downcase,\n      age: user['age'].to_i\n    }\n  end\n\n  def self.validate_user(user)\n    errors = []\n    errors &lt;&lt; 'Invalid email' unless user['email'].to_s.include?('@')\n    errors &lt;&lt; 'Invalid age' unless user['age'].to_i.positive?\n    errors &lt;&lt; 'Invalid name' unless user['name'].to_s.length &gt;= 2\n    errors\n  end\nend\n\n# \u4f7f\u7528\u4f8b\n# result = UserDataProcessor.process_csv('users.csv')\n# puts \"Valid users: #{result[:valid].length}\"\n# puts \"Invalid users: #{result[:invalid].length}\"<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-21\">\u8907\u96d1\u306a\u691c\u7d22\u30ed\u30b8\u30c3\u30af\u3092Enum\u3067\u6574\u7406\u3059\u308b<\/h3>\n\n\n\n<p>\u691c\u7d22\u30d5\u30a3\u30eb\u30bf\u30fc\u306e\u5b9f\u88c5\u4f8b\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 ProductSearch\n  def initialize(products)\n    @products = products\n  end\n\n  def search(params)\n    results = @products\n\n    results = filter_by_price(results, params[:price_range]) if params[:price_range]\n    results = filter_by_category(results, params[:category]) if params[:category]\n    results = filter_by_keyword(results, params[:keyword]) if params[:keyword]\n    results = sort_results(results, params[:sort_by]) if params[:sort_by]\n\n    results\n  end\n\n  private\n\n  def filter_by_price(products, range)\n    min, max = range.split('-').map(&amp;:to_i)\n    products.select { |p| p.price.between?(min, max) }\n  end\n\n  def filter_by_category(products, category)\n    products.select { |p| p.category == category }\n  end\n\n  def filter_by_keyword(products, keyword)\n    products.select { |p| \n      p.name.downcase.include?(keyword.downcase) ||\n      p.description.downcase.include?(keyword.downcase)\n    }\n  end\n\n  def sort_results(products, sort_by)\n    case sort_by\n    when 'price_asc'\n      products.sort_by(&amp;:price)\n    when 'price_desc'\n      products.sort_by(&amp;:price).reverse\n    when 'name'\n      products.sort_by(&amp;:name)\n    else\n      products\n    end\n  end\nend\n\n# \u4f7f\u7528\u4f8b\n# search = ProductSearch.new(Product.all)\n# results = search.search({\n#   price_range: '1000-5000',\n#   category: 'electronics',\n#   keyword: 'wireless',\n#   sort_by: 'price_asc'\n# })<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-22\">\u30d0\u30c3\u30c1\u51e6\u7406\u3067\u306eEnum\u6d3b\u7528\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>\u5927\u898f\u6a21\u306a\u30d0\u30c3\u30c1\u51e6\u7406\u306e\u5b9f\u88c5\u4f8b\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 BatchProcessor\n  class &lt;&lt; self\n    def process_in_batches(items, batch_size: 1000)\n      items\n        .each_slice(batch_size)\n        .with_index\n        .each_with_object({ success: [], failure: [] }) do |(batch, index), results|\n          begin\n            process_batch(batch, index, results)\n          rescue =&gt; e\n            log_error(e, batch, index)\n          end\n        end\n    end\n\n    private\n\n    def process_batch(batch, index, results)\n      puts \"Processing batch #{index + 1}...\"\n\n      batch.each do |item|\n        begin\n          processed_item = process_item(item)\n          results[:success] &lt;&lt; processed_item\n        rescue =&gt; e\n          results[:failure] &lt;&lt; {\n            item: item,\n            error: e.message\n          }\n        end\n      end\n    end\n\n    def process_item(item)\n      # \u5b9f\u969b\u306e\u51e6\u7406\u3092\u3053\u3053\u306b\u5b9f\u88c5\n      sleep(0.01) # \u51e6\u7406\u6642\u9593\u306e\u30b7\u30df\u30e5\u30ec\u30fc\u30b7\u30e7\u30f3\n      { id: item[:id], status: 'processed' }\n    end\n\n    def log_error(error, batch, index)\n      puts \"Error in batch #{index + 1}: #{error.message}\"\n      puts error.backtrace.take(5)\n    end\n  end\nend\n\n# \u4f7f\u7528\u4f8b\uff1a\u30ed\u30b0\u30d5\u30a1\u30a4\u30eb\u306e\u4e00\u62ec\u51e6\u7406\nclass LogProcessor\n  def self.process_logs(log_files)\n    log_files\n      .flat_map { |file| read_log_file(file) }\n      .group_by { |log| log[:event_type] }\n      .transform_values do |logs|\n        {\n          count: logs.length,\n          earliest: logs.min_by { |log| log[:timestamp] },\n          latest: logs.max_by { |log| log[:timestamp] },\n          error_rate: calculate_error_rate(logs)\n        }\n      end\n  end\n\n  private\n\n  def self.read_log_file(file)\n    File.readlines(file)\n      .map(&amp;:chomp)\n      .map { |line| parse_log_line(line) }\n      .compact\n  end\n\n  def self.parse_log_line(line)\n    timestamp, event_type, message = line.split('|').map(&amp;:strip)\n    {\n      timestamp: Time.parse(timestamp),\n      event_type: event_type,\n      message: message,\n      is_error: message.include?('ERROR')\n    }\n  rescue\n    nil\n  end\n\n  def self.calculate_error_rate(logs)\n    error_count = logs.count { |log| log[:is_error] }\n    (error_count.to_f \/ logs.length * 100).round(2)\n  end\nend\n\n# \u5b9f\u8df5\u7684\u306a\u30c7\u30fc\u30bf\u5909\u63db\u306e\u4f8b\nclass DataTransformer\n  def self.transform_records(records)\n    records\n      .group_by { |r| r[:date].to_date }\n      .transform_values do |daily_records|\n        {\n          total_amount: calculate_total(daily_records),\n          average_amount: calculate_average(daily_records),\n          transaction_count: daily_records.length,\n          categories: summarize_categories(daily_records)\n        }\n      end\n  end\n\n  private\n\n  def self.calculate_total(records)\n    records.sum { |r| r[:amount] }\n  end\n\n  def self.calculate_average(records)\n    return 0 if records.empty?\n    records.sum { |r| r[:amount] } \/ records.length.to_f\n  end\n\n  def self.summarize_categories(records)\n    records\n      .group_by { |r| r[:category] }\n      .transform_values { |rs| rs.sum { |r| r[:amount] } }\n  end\nend<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u88c5\u4f8b\u306f\u3001\u5b9f\u52d9\u3067\u906d\u9047\u3059\u308b\u5178\u578b\u7684\u306a\u30b7\u30ca\u30ea\u30aa\u306b\u5bfe\u3059\u308b\u89e3\u6c7a\u7b56\u3092\u63d0\u4f9b\u3057\u307e\u3059\u3002\u4ee5\u4e0b\u306e\u70b9\u306b\u6ce8\u610f\u3057\u3066\u5b9f\u88c5\u3057\u3066\u3044\u307e\u3059\uff1a<\/p>\n\n\n\n<ol 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