{"id":1258,"date":"2025-03-24T08:52:28","date_gmt":"2025-03-23T23:52:28","guid":{"rendered":"https:\/\/dexall.co.jp\/articles\/?p=1258"},"modified":"2025-03-24T08:52:28","modified_gmt":"2025-03-23T23:52:28","slug":"%e3%80%90ruby%e5%85%a5%e9%96%80%e3%80%91%e9%85%8d%e5%88%97%e3%81%aecompact%e3%83%a1%e3%82%bd%e3%83%83%e3%83%89%e3%81%ae%e5%ae%8c%e5%85%a8%e3%82%ac%e3%82%a4%e3%83%89%ef%bc%81%e4%bd%bf%e3%81%84%e6%96%b9","status":"publish","type":"post","link":"https:\/\/dexall.co.jp\/articles\/?p=1258","title":{"rendered":"\u3010Ruby\u5165\u9580\u3011\u914d\u5217\u306ecompact\u30e1\u30bd\u30c3\u30c9\u306e\u5b8c\u5168\u30ac\u30a4\u30c9\uff01\u4f7f\u3044\u65b9\u3068\u5b9f\u8df5\u7684\u306a7\u3064\u306e\u6d3b\u7528\u4f8b"},"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\">compact\u30e1\u30bd\u30c3\u30c9\u3068\u306f\uff1f\u57fa\u790e\u304b\u3089\u7406\u89e3\u3059\u308b\u4f7f\u3044\u65b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-1\">\u914d\u5217\u304b\u3089nil\u3092\u9664\u53bb\u3059\u308b\u30b7\u30f3\u30d7\u30eb\u306a\u65b9\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-2\">compact \u3068 compact! \u306e\u9055\u3044\u3092\u7406\u89e3\u3059\u308b<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-3\">compact\u30e1\u30bd\u30c3\u30c9\u306e\u7279\u5fb4\u3068\u6ce8\u610f\u70b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-4\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3078\u306e\u5f71\u97ff\u3092\u77e5\u308b<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-5\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u610f\u8b58\u3057\u305f\u4f7f\u3044\u65b9<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-6\">\u5b9f\u8df5\u7684\u306acompact\u30e1\u30bd\u30c3\u30c9\u306e\u6d3b\u7528\u4f8b<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-7\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u7d50\u679c\u306e\u30af\u30ea\u30fc\u30f3\u30a2\u30c3\u30d7<\/a>      <\/li>      <li>        <a href=\"#i-8\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6574\u5f62\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-9\">\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u30c7\u30fc\u30bf\u306e\u524d\u51e6\u7406\u306b\u6d3b\u7528<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-10\">compact\u30e1\u30bd\u30c3\u30c9\u3068\u7d44\u307f\u5408\u308f\u305b\u3066\u4f7f\u3048\u308b\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-11\">map \u3068 compact \u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u30c6\u30af\u30cb\u30c3\u30af<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-12\">select \u3084 reject \u3068\u306e\u4f75\u7528\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>    <\/ul>  <\/li>  <li>    <a href=\"#i-13\">compact\u30e1\u30bd\u30c3\u30c9\u306e\u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\u3068\u4ee3\u66ff\u6848<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-14\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u4f4e\u4e0b\u3055\u305b\u308b\u4f7f\u3044\u65b9\u3068\u305d\u306e\u6539\u5584\u65b9\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-15\">\u3088\u308a\u9069\u5207\u306a\u4ee3\u66ff\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u3073\u65b9<\/a>      <\/li>    <\/ul>  <\/li>  <li class=\"last\">    <a href=\"#i-16\">\u5b9f\u52d9\u3067\u4f7f\u3048\u308bcompact\u30e1\u30bd\u30c3\u30c9\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/a>    <ul class=\"menu_level_1\">      <li class=\"first\">        <a href=\"#i-17\">\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u3067\u3088\u304f\u4f7f\u3046\u30d1\u30bf\u30fc\u30f3<\/a>      <\/li>      <li>        <a href=\"#i-18\">\u30c6\u30b9\u30c8\u6642\u306e\u52b9\u679c\u7684\u306a\u6d3b\u7528\u65b9\u6cd5<\/a>      <\/li>      <li class=\"last\">        <a href=\"#i-19\">\u30c1\u30fc\u30e0\u958b\u767a\u3067\u306e\u547d\u540d\u898f\u5247\u3068\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u898f\u7d04<\/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\">compact\u30e1\u30bd\u30c3\u30c9\u3068\u306f\uff1f\u57fa\u790e\u304b\u3089\u7406\u89e3\u3059\u308b\u4f7f\u3044\u65b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-1\">\u914d\u5217\u304b\u3089nil\u3092\u9664\u53bb\u3059\u308b\u30b7\u30f3\u30d7\u30eb\u306a\u65b9\u6cd5<\/h3>\n\n\n\n<p>Ruby\u306e<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u914d\u5217\u304b\u3089<code>nil<\/code>\u8981\u7d20\u3092\u53d6\u308a\u9664\u3044\u3066\u65b0\u3057\u3044\u914d\u5217\u3092\u8fd4\u3059\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u3002\u30c7\u30fc\u30bf\u51e6\u7406\u3084API\u9023\u643a\u306b\u304a\u3044\u3066\u3001\u4e0d\u8981\u306a<code>nil<\/code>\u5024\u3092\u9664\u53bb\u3059\u308b\u969b\u306b\u3088\u304f\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9\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=\"\"># \u57fa\u672c\u7684\u306a\u4f7f\u7528\u4f8b\narray = [1, nil, 2, nil, 3]\nresult = array.compact\nputs result  # \u51fa\u529b: [1, 2, 3]\n\n# \u30cd\u30b9\u30c8\u3057\u305f\u914d\u5217\u3067\u306e\u4f7f\u7528\nnested_array = [1, [nil, 2], nil, 3]\nresult = nested_array.compact\nputs result  # \u51fa\u529b: [1, [nil, 2], 3]<\/pre>\n\n\n\n<p>\u6ce8\u76ee\u3059\u3079\u304d\u70b9\u3068\u3057\u3066\u3001<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u914d\u5217\u304b\u3089<code>nil<\/code>\u306e\u307f\u3092\u9664\u53bb\u3057\u307e\u3059<\/li>\n\n\n\n<li>false \u3084\u7a7a\u6587\u5b57\u5217\u30010\u306a\u3069\u306e\u5024\u306f\u4fdd\u6301\u3055\u308c\u307e\u3059<\/li>\n\n\n\n<li>\u30cd\u30b9\u30c8\u3057\u305f\u914d\u5217\u306e\u4e2d\u306e<code>nil<\/code>\u306f\u9664\u53bb\u3055\u308c\u307e\u305b\u3093<\/li>\n<\/ul>\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=\"\"># false\u3084\u7a7a\u6587\u5b57\u5217\u306f\u4fdd\u6301\u3055\u308c\u308b\narray = [1, nil, false, '', 0, nil]\nresult = array.compact\nputs result  # \u51fa\u529b: [1, false, '', 0]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-2\">compact \u3068 compact! \u306e\u9055\u3044\u3092\u7406\u89e3\u3059\u308b<\/h3>\n\n\n\n<p>Ruby\u306e<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u306f\u3001\u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9<code>compact!<\/code>\u3082\u7528\u610f\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u4e21\u8005\u306e\u4e3b\u306a\u9055\u3044\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><code>compact<\/code><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5143\u306e\u914d\u5217\u3092\u5909\u66f4\u305b\u305a\u3001\u65b0\u3057\u3044\u914d\u5217\u3092\u8fd4\u3057\u307e\u3059<\/li>\n\n\n\n<li>\u5e38\u306b\u65b0\u3057\u3044\u914d\u5217\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u751f\u6210\u3057\u307e\u3059<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306f\u5897\u52a0\u3057\u307e\u3059\u304c\u3001\u5b89\u5168\u3067\u3059<\/li>\n<\/ul>\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=\"\"># compact\u306e\u4f7f\u7528\u4f8b\noriginal = [1, nil, 2, nil]\nresult = original.compact\nputs original  # \u51fa\u529b: [1, nil, 2, nil]\nputs result   # \u51fa\u529b: [1, 2]\nputs original.object_id != result.object_id  # \u51fa\u529b: true<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><code>compact!<\/code><\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5143\u306e\u914d\u5217\u3092\u76f4\u63a5\u5909\u66f4\u3057\u307e\u3059<\/li>\n\n\n\n<li>nil\u304c\u542b\u307e\u308c\u3066\u3044\u306a\u3044\u5834\u5408\u306fnil\u3092\u8fd4\u3057\u307e\u3059<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u52b9\u7387\u304c\u826f\u3044\u3067\u3059\u304c\u3001\u4f7f\u7528\u6642\u306f\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059<\/li>\n<\/ul>\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=\"\"># compact!\u306e\u4f7f\u7528\u4f8b\narray = [1, nil, 2, nil]\nresult = array.compact!\nputs array   # \u51fa\u529b: [1, 2]\nputs result  # \u51fa\u529b: [1, 2]\nputs array.object_id == result.object_id  # \u51fa\u529b: true\n\n# nil\u304c\u306a\u3044\u5834\u5408\u306e\u52d5\u4f5c\narray = [1, 2, 3]\nresult = array.compact!\nputs result  # \u51fa\u529b: nil<\/pre>\n\n\n\n<p>\u5b9f\u52d9\u3067\u306e\u4f7f\u3044\u5206\u3051\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u306e\u53c2\u7167\u306e\u307f\u306e\u5834\u5408\u306f<code>compact<\/code>\u3092\u4f7f\u7528<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u52b9\u7387\u3092\u91cd\u8996\u3059\u308b\u5834\u5408\u3084\u3001\u5143\u306e\u914d\u5217\u3092\u66f4\u65b0\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u5834\u5408\u306f<code>compact!<\/code>\u3092\u4f7f\u7528<\/li>\n\n\n\n<li>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u3092\u884c\u3046\u5834\u5408\u306f<code>compact<\/code>\u306e\u4f7f\u7528\u3092\u63a8\u5968\uff08<code>compact!<\/code>\u304cnil\u3092\u8fd4\u3059\u53ef\u80fd\u6027\u304c\u3042\u308b\u305f\u3081\uff09<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u57fa\u672c\u3092\u62bc\u3055\u3048\u308b\u3053\u3068\u3067\u3001\u914d\u5217\u64cd\u4f5c\u306e\u52b9\u7387\u3092\u4e0a\u3052\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-3\">compact\u30e1\u30bd\u30c3\u30c9\u306e\u7279\u5fb4\u3068\u6ce8\u610f\u70b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-4\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3078\u306e\u5f71\u97ff\u3092\u77e5\u308b<\/h3>\n\n\n\n<p><code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u7279\u6027\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u306f\u3001\u5927\u898f\u6a21\u306a\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u958b\u767a\u306b\u304a\u3044\u3066\u91cd\u8981\u3067\u3059\u3002\u4ee5\u4e0b\u306b\u4e3b\u8981\u306a\u30dd\u30a4\u30f3\u30c8\u3092\u307e\u3068\u3081\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u6642\u9593\u8a08\u7b97\u91cf<\/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\n# \u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30c6\u30b9\u30c8\u7528\u306e\u914d\u5217\u3092\u751f\u6210\nsmall_array = Array.new(1000) { |i| i % 3 == 0 ? nil : i }\nlarge_array = Array.new(1000000) { |i| i % 3 == 0 ? nil : i }\n\nBenchmark.bm do |x|\n  x.report(\"small array:\") { small_array.compact }\n  x.report(\"large array:\") { large_array.compact }\nend<\/pre>\n\n\n\n<p>\u4e3b\u306a\u7279\u5fb4\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u914d\u5217\u306e\u8981\u7d20\u6570\u306b\u6bd4\u4f8b\u3059\u308b O(n) \u306e\u6642\u9593\u8a08\u7b97\u91cf<\/li>\n\n\n\n<li>\u5404\u8981\u7d20\u306b\u5bfe\u3057\u30661\u56de\u3060\u3051\u306e\u8d70\u67fb\u3067\u5b8c\u4e86<\/li>\n\n\n\n<li><code>nil<\/code>\u30c1\u30a7\u30c3\u30af\u306f\u9ad8\u901f\u306a\u6f14\u7b97\u3067\u5b9f\u884c\u3055\u308c\u308b<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-5\">\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u3092\u610f\u8b58\u3057\u305f\u4f7f\u3044\u65b9<\/h3>\n\n\n\n<p>\u30e1\u30e2\u30ea\u4f7f\u7528\u306e\u89b3\u70b9\u304b\u3089\u3001<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306b\u306f\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>\u30e1\u30e2\u30ea\u30a2\u30ed\u30b1\u30fc\u30b7\u30e7\u30f3<\/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\u306e\u9055\u3044\u3092\u78ba\u8a8d\narray = Array.new(1000000) { |i| i % 2 == 0 ? nil : i }\n\n# compact\u4f7f\u7528\u6642\u306e\u30e1\u30e2\u30ea\u5272\u308a\u5f53\u3066\nmemory_before = `ps -o rss= -p #{Process.pid}`.to_i\nresult = array.compact\nmemory_after = `ps -o rss= -p #{Process.pid}`.to_i\nputs \"Memory difference: #{memory_after - memory_before} KB\"<\/pre>\n\n\n\n<p>\u52b9\u7387\u7684\u306a\u30e1\u30e2\u30ea\u4f7f\u7528\u306e\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>\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u51e6\u7406\u6642\u306e\u6ce8\u610f\u70b9<\/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=\"\"># \u63a8\u5968\uff1a\u5fc5\u8981\u306a\u5834\u5408\u306e\u307fcompact!\u3092\u4f7f\u7528\nlarge_array = Array.new(1000000) { |i| i % 2 == 0 ? nil : i }\nlarge_array.compact! if large_array.include?(nil)\n\n# \u975e\u63a8\u5968\uff1a\u4e0d\u5fc5\u8981\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u751f\u6210\nresult = large_array.compact # \u65b0\u3057\u3044\u914d\u5217\u3092\u751f\u6210<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30e1\u30e2\u30ea\u30ea\u30fc\u30af\u306e\u9632\u6b62<\/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\u3044\u4f8b\uff1a\u5fc5\u8981\u306a\u30b9\u30b3\u30fc\u30d7\u3067\u51e6\u7406\ndef process_data(array)\n  array.compact\nend\n\n# \u907f\u3051\u308b\u3079\u304d\u4f8b\uff1a\u4e0d\u8981\u306a\u30e1\u30e2\u30ea\u4fdd\u6301\n@processed_array = array.compact # \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u5909\u6570\u306b\u4fdd\u6301<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u7279\u5fb4\u3068\u6ce8\u610f\u70b9\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u52b9\u7387\u7684\u306a\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u3001\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u6700\u9069\u5316\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u6b21\u306e\u30bb\u30af\u30b7\u30e7\u30f3\u306b\u9032\u3080\u524d\u306b\u3001\u3053\u308c\u3089\u306e\u70b9\u306b\u3064\u3044\u3066\u4f55\u304b\u8cea\u554f\u306f\u3042\u308a\u307e\u3059\u304b\uff1f<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-6\">\u5b9f\u8df5\u7684\u306acompact\u30e1\u30bd\u30c3\u30c9\u306e\u6d3b\u7528\u4f8b<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-7\">\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u30af\u30a8\u30ea\u7d50\u679c\u306e\u30af\u30ea\u30fc\u30f3\u30a2\u30c3\u30d7<\/h3>\n\n\n\n<p>ActiveRecord\u3092\u4f7f\u7528\u3057\u305f\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u64cd\u4f5c\u3067\u306f\u3001<code>nil<\/code>\u5024\u3092\u542b\u3080\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u6a5f\u4f1a\u304c\u591a\u304f\u3042\u308a\u307e\u3059\u3002\u4ee5\u4e0b\u306b\u5b9f\u8df5\u7684\u306a\u4f8b\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=\"\">class User &lt; ApplicationRecord\n  has_many :orders\n  has_one :profile\n\n  def self.active_users_with_orders\n    # \u30d7\u30ed\u30d5\u30a3\u30fc\u30eb\u60c5\u5831\u3068\u6ce8\u6587\u60c5\u5831\u3092\u6301\u3064\u30e6\u30fc\u30b6\u30fc\u306e\u307f\u3092\u53d6\u5f97\n    users = includes(:profile, :orders).map do |user|\n      {\n        id: user.id,\n        name: user.profile&amp;.name,\n        latest_order: user.orders.last&amp;.created_at\n      }\n    end\n\n    # nil\u5024\u3092\u542b\u3080\u30c7\u30fc\u30bf\u3092\u30af\u30ea\u30fc\u30f3\u30a2\u30c3\u30d7\n    users.compact\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-8\">API\u30ec\u30b9\u30dd\u30f3\u30b9\u306e\u6574\u5f62\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p>\u5916\u90e8API\u3068\u306e\u9023\u643a\u6642\u306b\u3001\u30ec\u30b9\u30dd\u30f3\u30b9\u30c7\u30fc\u30bf\u304b\u3089\u4e0d\u8981\u306a<code>nil<\/code>\u5024\u3092\u9664\u53bb\u3059\u308b\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=\"\">class ApiResponseHandler\n  def self.process_user_data(api_response)\n    users = api_response['users'].map do |user|\n      {\n        id: user['id'],\n        email: user['email'],\n        name: user.dig('profile', 'name'),\n        address: user.dig('profile', 'address'),\n        phone: user.dig('contact', 'phone')\n      }\n    end\n\n    # nil\u5024\u3092\u542b\u3080\u30d5\u30a3\u30fc\u30eb\u30c9\u3092\u9664\u53bb\n    users.map { |user| user.compact }\n  end\nend\n\n# \u4f7f\u7528\u4f8b\nresponse = {\n  'users' =&gt; [\n    {\n      'id' =&gt; 1,\n      'email' =&gt; 'user1@example.com',\n      'profile' =&gt; { 'name' =&gt; 'User 1' }\n    }\n  ]\n}\ncleaned_data = ApiResponseHandler.process_user_data(response)<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-9\">\u30e6\u30fc\u30b6\u30fc\u5165\u529b\u30c7\u30fc\u30bf\u306e\u524d\u51e6\u7406\u306b\u6d3b\u7528<\/h3>\n\n\n\n<p>\u30d5\u30a9\u30fc\u30e0\u304b\u3089\u306e\u5165\u529b\u30c7\u30fc\u30bf\u3092\u51e6\u7406\u3059\u308b\u969b\u306e\u6d3b\u7528\u4f8b\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=\"\">class FormDataProcessor\n  def self.clean_user_input(params)\n    # \u7a7a\u6587\u5b57\u3092nil\u306b\u5909\u63db\u3057\u3001\u4e0d\u8981\u306a\u30c7\u30fc\u30bf\u3092\u9664\u53bb\n    cleaned_params = params.transform_values { |v| v.presence }\n    cleaned_params.compact\n  end\n\n  def self.process_csv_import(csv_data)\n    rows = csv_data.map do |row|\n      {\n        name: row['Name']&amp;.strip,\n        email: row['Email']&amp;.downcase,\n        age: row['Age']&amp;.to_i,\n        notes: row['Notes']&amp;.presence\n      }\n    end\n\n    # \u5fc5\u9808\u30d5\u30a3\u30fc\u30eb\u30c9\u304cnil\u306e\u30c7\u30fc\u30bf\u3092\u9664\u53bb\n    rows.compact\n  end\nend\n\n# \u4f7f\u7528\u4f8b\nparams = {\n  \"name\" =&gt; \"  John  \",\n  \"email\" =&gt; \"\",\n  \"age\" =&gt; \"25\",\n  \"notes\" =&gt; nil\n}\ncleaned_params = FormDataProcessor.clean_user_input(params)<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u8df5\u4f8b\u304b\u3089\u308f\u304b\u308b\u3088\u3046\u306b\u3001<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306f\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u306e\u30af\u30ea\u30fc\u30f3\u30a2\u30c3\u30d7<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e0d\u5b8c\u5168\u306a\u30ec\u30b3\u30fc\u30c9\u306e\u9664\u53bb<\/li>\n\n\n\n<li>\u5fc5\u9808\u30d5\u30a3\u30fc\u30eb\u30c9\u306e\u691c\u8a3c<\/li>\n\n\n\n<li>\u30c7\u30fc\u30bf\u306e\u6b63\u898f\u5316<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u6700\u9069\u5316<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e0d\u8981\u306a\u30c7\u30fc\u30bf\u306e\u65e9\u671f\u9664\u53bb<\/li>\n\n\n\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\u524a\u6e1b<\/li>\n\n\n\n<li>\u5f8c\u7d9a\u306e\u51e6\u7406\u306e\u52b9\u7387\u5316<\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30c7\u30fc\u30bf\u306e\u54c1\u8cea\u5411\u4e0a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e00\u8cab\u6027\u306e\u3042\u308b\u30c7\u30fc\u30bf\u69cb\u9020\u306e\u7dad\u6301<\/li>\n\n\n\n<li>\u30a8\u30e9\u30fc\u306e\u4e8b\u524d\u9632\u6b62<\/li>\n\n\n\n<li>\u30c7\u30d0\u30c3\u30b0\u306e\u5bb9\u6613\u5316<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u5b9f\u8df5\u7684\u306a\u4f8b\u3092\u53c2\u8003\u306b\u3001\u81ea\u8eab\u306e\u30d7\u30ed\u30b8\u30a7\u30af\u30c8\u3067\u3082\u52b9\u679c\u7684\u306b<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u6d3b\u7528\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"i-10\">compact\u30e1\u30bd\u30c3\u30c9\u3068\u7d44\u307f\u5408\u308f\u305b\u3066\u4f7f\u3048\u308b\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-11\">map \u3068 compact \u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u30c6\u30af\u30cb\u30c3\u30af<\/h3>\n\n\n\n<p><code>map<\/code>\u3068<code>compact<\/code>\u306e\u7d44\u307f\u5408\u308f\u305b\u306f\u3001\u30c7\u30fc\u30bf\u5909\u63db\u3068<code>nil<\/code>\u5024\u306e\u9664\u53bb\u3092\u52b9\u7387\u7684\u306b\u884c\u3046\u5f37\u529b\u306a\u30d1\u30bf\u30fc\u30f3\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=\"\"># \u57fa\u672c\u7684\u306a\u7d44\u307f\u5408\u308f\u305b\u4f8b\nnumbers = [1, 2, nil, 3, nil, 4]\nresult = numbers.map { |n| n&amp;.* 2 }.compact\nputs result  # \u51fa\u529b: [2, 4, 6, 8]\n\n# \u3088\u308a\u5b9f\u8df5\u7684\u306a\u4f8b\uff1a\u30e6\u30fc\u30b6\u30fc\u30c7\u30fc\u30bf\u306e\u51e6\u7406\nclass User\n  attr_reader :name, :email\n\n  def initialize(name, email)\n    @name = name\n    @email = email\n  end\nend\n\nusers = [\n  User.new(\"John\", \"john@example.com\"),\n  nil,\n  User.new(\"Alice\", nil),\n  User.new(\"Bob\", \"bob@example.com\")\n]\n\n# \u30e1\u30fc\u30eb\u30a2\u30c9\u30ec\u30b9\u306e\u3042\u308b\u6709\u52b9\u306a\u30e6\u30fc\u30b6\u30fc\u306e\u307f\u3092\u62bd\u51fa\nvalid_emails = users.map { |user| user&amp;.email }.compact\nputs valid_emails  # \u51fa\u529b: [\"john@example.com\", \"bob@example.com\"]<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-12\">select \u3084 reject \u3068\u306e\u4f75\u7528\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p><code>select<\/code>\u3084<code>reject<\/code>\u3068<code>compact<\/code>\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u67d4\u8edf\u306a\u30c7\u30fc\u30bf\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\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=\"\"># select\u3068compact\u306e\u7d44\u307f\u5408\u308f\u305b\ndata = [1, nil, 2, nil, 3, 4, nil, 5]\nresult = data.compact.select { |n| n &gt; 2 }\nputs result  # \u51fa\u529b: [3, 4, 5]\n\n# \u3088\u308a\u5b9f\u8df5\u7684\u306a\u4f8b\uff1a\u6761\u4ef6\u4ed8\u304d\u30c7\u30fc\u30bf\u62bd\u51fa\nclass Order\n  attr_reader :id, :status, :amount\n\n  def initialize(id, status, amount)\n    @id = id\n    @status = status\n    @amount = amount\n  end\nend\n\norders = [\n  Order.new(1, \"pending\", 100),\n  nil,\n  Order.new(2, \"completed\", nil),\n  Order.new(3, \"completed\", 300)\n]\n\n# \u5b8c\u4e86\u6e08\u307f\u3067\u91d1\u984d\u304c\u8a2d\u5b9a\u3055\u308c\u3066\u3044\u308b\u6ce8\u6587\u306e\u307f\u3092\u62bd\u51fa\nvalid_orders = orders.compact.select { |order| \n  order.status == \"completed\" &amp;&amp; order.amount\n}\n\n# reject\u3068compact\u306e\u7d44\u307f\u5408\u308f\u305b\nnumbers = [1, nil, 2, nil, 3, 4, nil, 5]\nresult = numbers.compact.reject { |n| n.even? }\nputs result  # \u51fa\u529b: [1, 3, 5]<\/pre>\n\n\n\n<p>\u30e1\u30bd\u30c3\u30c9\u30c1\u30a7\u30fc\u30f3\u3092\u4f7f\u7528\u3059\u308b\u969b\u306e\u6700\u9069\u5316\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u51e6\u7406\u9806\u5e8f\u306e\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=\"\"># \u63a8\u5968\uff1a\u65e9\u671f\u306b\u30c7\u30fc\u30bf\u91cf\u3092\u6e1b\u3089\u3059\nusers.compact.select { |u| u.active? }.map { |u| u.email }\n\n# \u975e\u63a8\u5968\uff1a\u4e0d\u8981\u306a\u30a4\u30c6\u30ec\u30fc\u30b7\u30e7\u30f3\u304c\u767a\u751f\nusers.map { |u| u&amp;.email if u&amp;.active? }.compact<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u8003\u616e\u3057\u305f\u30c1\u30a7\u30fc\u30f3<\/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\u898f\u6a21\u30c7\u30fc\u30bf\u30bb\u30c3\u30c8\u5411\u3051\u306e\u52b9\u7387\u7684\u306a\u51e6\u7406\nlarge_dataset.compact!  # \u307e\u305a\u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\u3067\u30e1\u30e2\u30ea\u3092\u7bc0\u7d04\n  .select! { |item| item.valid? }  # \u5fc5\u8981\u306a\u30c7\u30fc\u30bf\u306e\u307f\u3092\u4fdd\u6301\n  .map! { |item| item.transform }  # \u6700\u7d42\u7684\u306a\u5909\u63db\u3092\u5b9f\u884c<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u7d44\u307f\u5408\u308f\u305b\u30d1\u30bf\u30fc\u30f3\u3092\u7406\u89e3\u3057\u9069\u5207\u306b\u4f7f\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u7c21\u6f54\u3067\u4fdd\u5b88\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-13\">compact\u30e1\u30bd\u30c3\u30c9\u306e\u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\u3068\u4ee3\u66ff\u6848<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-14\">\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u4f4e\u4e0b\u3055\u305b\u308b\u4f7f\u3044\u65b9\u3068\u305d\u306e\u6539\u5584\u65b9\u6cd5<\/h3>\n\n\n\n<p><code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u975e\u52b9\u7387\u306a\u4f7f\u7528\u30d1\u30bf\u30fc\u30f3\u3068\u305d\u306e\u6539\u5584\u65b9\u6cd5\u3092\u898b\u3066\u3044\u304d\u307e\u3057\u3087\u3046\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4e0d\u5fc5\u8981\u306a\u7e70\u308a\u8fd4\u3057\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=\"\"># \u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\uff1a\u7121\u99c4\u306acompact\u306e\u5b9f\u884c\ndef process_user_data(users)\n  users.map { |user| user.name }.compact.map { |name| name.upcase }.compact\nend\n\n# \u6539\u5584\u6848\uff1a1\u56de\u306e\u51e6\u7406\u306b\u307e\u3068\u3081\u308b\ndef process_user_data(users)\n  users.map { |user| user&amp;.name&amp;.upcase }.compact\nend\n\n# \u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6bd4\u8f03\nusers = Array.new(10000) { |i| OpenStruct.new(name: i.even? ? \"user#{i}\" : nil) }\n\nBenchmark.bm do |x|\n  x.report(\"\u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3:\") { process_user_data(users) }\n  x.report(\"\u6539\u5584\u6848:\") { process_user_data(users) }\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30e1\u30e2\u30ea\u975e\u52b9\u7387\u306a\u4f7f\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=\"\"># \u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\uff1a\u4e0d\u8981\u306a\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u751f\u6210\ndef clean_large_dataset(data)\n  temp_data = data.compact  # \u65b0\u3057\u3044\u914d\u5217\u3092\u751f\u6210\n  temp_data.map! { |item| item * 2 }  # \u3055\u3089\u306b\u51e6\u7406\u3092\u8ffd\u52a0\n  temp_data\nend\n\n# \u6539\u5584\u6848\uff1a\u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\u3092\u9069\u5207\u306b\u4f7f\u7528\ndef clean_large_dataset(data)\n  data.compact!  # \u540c\u3058\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u66f4\u65b0\n  data.map! { |item| item * 2 }\n  data\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li>\u6761\u4ef6\u5206\u5c90\u306e\u8aa4\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=\"\"># \u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\uff1acompact\u3092\u4f7f\u3063\u305f\u6761\u4ef6\u5206\u5c90\ndef get_user_status(user)\n  [user&amp;.active? ? user.status : nil].compact.first || 'inactive'\nend\n\n# \u6539\u5584\u6848\uff1a\u5358\u7d14\u306a\u6761\u4ef6\u5206\u5c90\u3092\u4f7f\u7528\ndef get_user_status(user)\n  user&amp;.active? ? user.status : 'inactive'\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-15\">\u3088\u308a\u9069\u5207\u306a\u4ee3\u66ff\u30e1\u30bd\u30c3\u30c9\u306e\u9078\u3073\u65b9<\/h3>\n\n\n\n<p>\u72b6\u6cc1\u306b\u5fdc\u3058\u3066\u3001<code>compact<\/code>\u306e\u4ee3\u308f\u308a\u306b\u4f7f\u7528\u3067\u304d\u308b\u9069\u5207\u306a\u30e1\u30bd\u30c3\u30c9\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><code>reject<\/code>\u3092\u4f7f\u7528\u3057\u305fnil\u9664\u53bb<\/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=\"\"># compact\u3092\u4f7f\u7528\u3059\u308b\u5834\u5408\narray = [1, nil, 2, nil, 3]\nresult = array.compact\n\n# reject\u3092\u4f7f\u7528\u3059\u308b\u4ee3\u66ff\u6848\nresult = array.reject(&amp;:nil?)<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li><code>select<\/code>\u3092\u4f7f\u7528\u3057\u305f\u5024\u306e\u62bd\u51fa<\/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=\"\"># \u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\uff1a\u4e0d\u8981\u306acompact\u306e\u4f7f\u7528\ndef active_users(users)\n  users.map { |user| user if user&amp;.active? }.compact\nend\n\n# \u6539\u5584\u6848\uff1aselect\u3092\u76f4\u63a5\u4f7f\u7528\ndef active_users(users)\n  users.select(&amp;:active?)\nend<\/pre>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><code>reduce<\/code>\u3092\u4f7f\u7528\u3057\u305f\u30c7\u30fc\u30bf\u96c6\u7d04<\/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=\"\"># \u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\uff1a\u914d\u5217\u751f\u6210\u3068compact\u306e\u7d44\u307f\u5408\u308f\u305b\ndef sum_valid_numbers(numbers)\n  numbers.map { |n| n.is_a?(Numeric) ? n : nil }.compact.sum\nend\n\n# \u6539\u5584\u6848\uff1areduce\u3092\u4f7f\u7528\u3057\u305f\u76f4\u63a5\u7684\u306a\u96c6\u7d04\ndef sum_valid_numbers(numbers)\n  numbers.reduce(0) { |sum, n| n.is_a?(Numeric) ? sum + n : sum }\nend<\/pre>\n\n\n\n<p>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6539\u5584\u306e\u30dd\u30a4\u30f3\u30c8\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u65e9\u671f\u30ea\u30bf\u30fc\u30f3<\/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=\"\"># \u6539\u5584\u524d\uff1a\u4e0d\u8981\u306acompact\u306e\u5b9f\u884c\ndef find_first_valid(items)\n  items.map { |item| valid?(item) ? item : nil }.compact.first\nend\n\n# \u6539\u5584\u5f8c\uff1a\u691c\u51fa\u6b21\u7b2c\u30ea\u30bf\u30fc\u30f3\ndef find_first_valid(items)\n  items.find { |item| valid?(item) }\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30e1\u30e2\u30ea\u4f7f\u7528\u91cf\u306e\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=\"\"># \u6539\u5584\u524d\uff1a\u5927\u91cf\u306e\u30e1\u30e2\u30ea\u5272\u308a\u5f53\u3066\ndef process_large_data(items)\n  items.map { |item| transform(item) }.compact\nend\n\n# \u6539\u5584\u5f8c\uff1aEnumerator\u3092\u4f7f\u7528\ndef process_large_data(items)\n  Enumerator.new do |yielder|\n    items.each do |item|\n      result = transform(item)\n      yielder &lt;&lt; result if result\n    end\n  end\nend<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30a2\u30f3\u30c1\u30d1\u30bf\u30fc\u30f3\u3068\u6539\u5584\u65b9\u6cd5\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u52b9\u7387\u7684\u3067\u4fdd\u5b88\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-16\">\u5b9f\u52d9\u3067\u4f7f\u3048\u308bcompact\u30e1\u30bd\u30c3\u30c9\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-17\">\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u3067\u3088\u304f\u4f7f\u3046\u30d1\u30bf\u30fc\u30f3<\/h3>\n\n\n\n<p>\u5b9f\u52d9\u3067\u306e\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u6642\u306b\u6d3b\u7528\u3067\u304d\u308b<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u30d1\u30bf\u30fc\u30f3\u3092\u7d39\u4ecb\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u6761\u4ef6\u5206\u5c90\u306e\u7c21\u7d20\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=\"\"># \u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u524d\ndef get_user_data(user)\n  if user\n    if user.profile\n      {\n        name: user.profile.name,\n        email: user.profile.email\n      }\n    end\n  end\nend\n\n# \u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u5f8c\ndef get_user_data(user)\n  {\n    name: user&amp;.profile&amp;.name,\n    email: user&amp;.profile&amp;.email\n  }.compact\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u51e6\u7406\u306e\u6539\u5584<\/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=\"\">class User &lt; ApplicationRecord\n  # \u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u524d\n  def valid_profile?\n    profile &amp;&amp; \n    profile.name &amp;&amp; \n    profile.email &amp;&amp;\n    profile.age\n  end\n\n  # \u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u5f8c\n  def valid_profile?\n    [\n      profile&amp;.name,\n      profile&amp;.email,\n      profile&amp;.age\n    ].compact.size == 3\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-18\">\u30c6\u30b9\u30c8\u6642\u306e\u52b9\u679c\u7684\u306a\u6d3b\u7528\u65b9\u6cd5<\/h3>\n\n\n\n<p><code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3059\u308b\u30b3\u30fc\u30c9\u306e\u30c6\u30b9\u30c8\u65b9\u6cd5\u3068\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\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=\"\">RSpec.describe ArrayProcessor do\n  describe '#clean_data' do\n    let(:processor) { ArrayProcessor.new }\n\n    context '\u6b63\u5e38\u7cfb\u306e\u30c6\u30b9\u30c8' do\n      it 'nil\u3092\u9664\u53bb\u3057\u3066\u6709\u52b9\u306a\u30c7\u30fc\u30bf\u306e\u307f\u3092\u8fd4\u3059\u3053\u3068' do\n        input = [1, nil, 2, nil, 3]\n        expect(processor.clean_data(input)).to eq([1, 2, 3])\n      end\n\n      it '\u7a7a\u306e\u914d\u5217\u306e\u5834\u5408\u306f\u7a7a\u914d\u5217\u3092\u8fd4\u3059\u3053\u3068' do\n        expect(processor.clean_data([])).to eq([])\n      end\n\n      it 'nil\u4ee5\u5916\u306e falsey \u306a\u5024\u306f\u4fdd\u6301\u3055\u308c\u308b\u3053\u3068' do\n        input = [1, nil, false, '', 0]\n        expect(processor.clean_data(input)).to eq([1, false, '', 0])\n      end\n    end\n\n    context '\u30a8\u30c3\u30b8\u30b1\u30fc\u30b9' do\n      it '\u30cd\u30b9\u30c8\u3057\u305f\u914d\u5217\u306enil\u306f\u9664\u53bb\u3055\u308c\u306a\u3044\u3053\u3068' do\n        input = [1, [nil, 2], 3]\n        expect(processor.clean_data(input)).to eq([1, [nil, 2], 3])\n      end\n    end\n  end\nend<\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"i-19\">\u30c1\u30fc\u30e0\u958b\u767a\u3067\u306e\u547d\u540d\u898f\u5247\u3068\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u898f\u7d04<\/h3>\n\n\n\n<p>\u30c1\u30fc\u30e0\u958b\u767a\u306b\u304a\u3051\u308b<code>compact<\/code>\u30e1\u30bd\u30c3\u30c9\u306e\u4f7f\u7528\u30ac\u30a4\u30c9\u30e9\u30a4\u30f3\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u30e1\u30bd\u30c3\u30c9\u547d\u540d\u898f\u5247<\/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=\"\"># \u63a8\u5968\uff1a\u76ee\u7684\u304c\u660e\u78ba\u306a\u547d\u540d\ndef clean_user_attributes\n  attributes.compact\nend\n\ndef remove_invalid_records\n  records.compact\nend\n\n# \u975e\u63a8\u5968\uff1a\u62bd\u8c61\u7684\u3059\u304e\u308b\u547d\u540d\ndef process_data\n  data.compact\nend<\/pre>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\">\n<li>\u30b3\u30e1\u30f3\u30c8\u8a18\u8ff0\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9<\/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=\"\">class DataProcessor\n  # nil\u3092\u9664\u53bb\u3057\u3066\u6709\u52b9\u306a\u30ec\u30b3\u30fc\u30c9\u306e\u307f\u3092\u8fd4\u3059\n  # @param records [Array&lt;Record&gt;] \u51e6\u7406\u5bfe\u8c61\u306e\u30ec\u30b3\u30fc\u30c9\u914d\u5217\n  # @return [Array&lt;Record&gt;] nil\u4ee5\u5916\u306e\u30ec\u30b3\u30fc\u30c9\u914d\u5217\n  def clean_records(records)\n    records.compact\n  end\n\n  # \u30ec\u30b3\u30fc\u30c9\u306e\u7279\u5b9a\u5c5e\u6027\u304b\u3089nil\u3092\u9664\u53bb\u3059\u308b\n  # @param records [Array&lt;Record&gt;] \u51e6\u7406\u5bfe\u8c61\u306e\u30ec\u30b3\u30fc\u30c9\u914d\u5217\n  # @param attributes [Array&lt;Symbol&gt;] \u5bfe\u8c61\u306e\u5c5e\u6027\u540d\u914d\u5217\n  # @return [Array&lt;Hash&gt;] \u6709\u52b9\u306a\u5c5e\u6027\u306e\u307f\u3092\u542b\u3080\u30cf\u30c3\u30b7\u30e5\u914d\u5217\n  def extract_valid_attributes(records, attributes)\n    records.map do |record|\n      attributes.map { |attr| <\/pre>\n\n\n[attr, record.public_send(attr)]\n\n\n\n<p>}.to_h.compact end end end<\/p>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li>\u30b3\u30fc\u30c9\u30ec\u30d3\u30e5\u30fc\u306e\u30c1\u30a7\u30c3\u30af\u30dd\u30a4\u30f3\u30c8<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u306e\u8003\u616e<\/li>\n<\/ul>\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=\"\">  # \u30ec\u30d3\u30e5\u30fc\u5bfe\u8c61\uff1a\u5927\u898f\u6a21\u30c7\u30fc\u30bf\u306e\u51e6\u7406\n  def process_large_dataset(data)\n    return [] if data.empty?\n\n    # \u51e6\u7406\u524d\u306b\u30c7\u30fc\u30bf\u30b5\u30a4\u30ba\u3092\u30ed\u30b0\u51fa\u529b\n    Rails.logger.info \"Processing #{data.size} records\"\n\n    # \u7834\u58ca\u7684\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u7528\u3057\u3066\u30e1\u30e2\u30ea\u4f7f\u7528\u3092\u6700\u9069\u5316\n    data.compact!\n    data.map! { |item| transform_item(item) }\n\n    # \u51e6\u7406\u5f8c\u306e\u30c7\u30fc\u30bf\u30b5\u30a4\u30ba\u3092\u30ed\u30b0\u51fa\u529b\n    Rails.logger.info \"Processed #{data.size} valid records\"\n    data\n  end<\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30a8\u30e9\u30fc\u30cf\u30f3\u30c9\u30ea\u30f3\u30b0<\/li>\n<\/ul>\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=\"\">  def safe_compact(array)\n    array.compact\n  rescue NoMethodError\n    Rails.logger.error \"Invalid input: array must respond to compact\"\n    []\n  end<\/pre>\n\n\n\n<p>\u3053\u308c\u3089\u306e\u30d9\u30b9\u30c8\u30d7\u30e9\u30af\u30c6\u30a3\u30b9\u3092\u9069\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u30e1\u30f3\u30c6\u30ca\u30f3\u30b9\u6027\u304c\u9ad8\u304f\u3001\u30c1\u30fc\u30e0\u3067\u6271\u3044\u3084\u3059\u3044\u30b3\u30fc\u30c9\u3092\u66f8\u304f\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002\u307e\u305f\u3001\u5c06\u6765\u7684\u306a\u30ea\u30d5\u30a1\u30af\u30bf\u30ea\u30f3\u30b0\u3084\u30c7\u30d0\u30c3\u30b0\u3082\u5bb9\u6613\u306b\u306a\u308a\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":[1],"tags":[],"class_list":{"0":"post-1258","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-uncategorized","7":"nothumb"},"_links":{"self":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1258","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=1258"}],"version-history":[{"count":1,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1258\/revisions"}],"predecessor-version":[{"id":1259,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=\/wp\/v2\/posts\/1258\/revisions\/1259"}],"wp:attachment":[{"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1258"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1258"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dexall.co.jp\/articles\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1258"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}