{"id":695,"date":"2024-07-10T18:00:00","date_gmt":"2024-07-10T09:00:00","guid":{"rendered":"https:\/\/blog.fundely.co.jp\/tech\/?p=695"},"modified":"2024-07-03T11:09:07","modified_gmt":"2024-07-03T02:09:07","slug":"reselect-%e3%81%ae%e4%bb%95%e7%b5%84%e3%81%bf%e3%81%a8%e4%bd%bf%e3%81%84%e6%96%b9","status":"publish","type":"post","link":"https:\/\/blog.fundely.co.jp\/tech\/2024\/07\/10\/reselect-%e3%81%ae%e4%bb%95%e7%b5%84%e3%81%bf%e3%81%a8%e4%bd%bf%e3%81%84%e6%96%b9\/","title":{"rendered":"reselect \u306e\u4ed5\u7d44\u307f\u3068\u4f7f\u3044\u65b9"},"content":{"rendered":"\n

<\/p>\n\n\n\n

\u80cc\u666f<\/h3>\n\n\n\n

Redux\u306e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u898b\u3066\u3044\u308b\u3068\u300creselect\u300d\u3068\u3044\u3046\u30e9\u30a4\u30d6\u30e9\u30ea\u306b\u3064\u3044\u3066\u66f8\u304b\u308c\u3066\u304a\u308a\u3001\u3046\u307e\u304f\u5229\u7528\u3059\u308c\u3070\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30c1\u30e5\u30fc\u30cb\u30f3\u30b0\uff08\u30b7\u30b9\u30c6\u30e0\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u5411\u4e0a\u3055\u305b\u308b\u3053\u3068\uff09\u3067\u304d\u308b\u3053\u3068\u3092\u77e5\u308a\u307e\u3057\u305f\u3002<\/p>\n\n\n\n

\u4eca\u56de \u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u8aad\u307f\u9032\u3081\u3066\u3044\u304f\u4e2d\u3067 reselect \u306b\u3064\u3044\u3066\u3044\u308d\u3044\u308d\u306a\u3053\u3068\u3092\u77e5\u308a\u3001\u81ea\u5206\u306a\u308a\u306b\u4f7f\u7528\u65b9\u6cd5\u3084reselect\u306e\u5185\u90e8\u3067\u8d77\u304d\u3066\u3044\u308b\u30e1\u30e2\u5316\u306b\u3064\u3044\u3066\u308f\u304b\u308a\u3084\u3059\u304f\u307e\u3068\u3081\u3066\u307f\u307e\u3057\u305f\u3002<\/p>\n\n\n\n

\u3053\u308c\u304b\u3089reselect\u3092\u4f7f\u7528\u3059\u308b\u4eba\u306e\u53c2\u8003\u306b\u306a\u308c\u3070\u5e78\u3044\u3067\u3059\u3002<\/p>\n\n\n\n

<\/p>\n\n\n\n

reselect \u3068\u306f\uff1f<\/h3>\n\n\n\n

reselect<\/a> \u3068\u306f\u30e1\u30e2\u5316\uff08\u5909\u6570\u30fb\u95a2\u6570\u30fb\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306e\u30ad\u30e3\u30c3\u30b7\u30e5\u3092\u518d\u5229\u7528\u3057\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306e\u4e0d\u8981\u306a\u518d\u30ec\u30f3\u30c0\u30ea\u30f3\u30b0\u3092\u6291\u3048\u308b\u3053\u3068\uff09\u3055\u308c\u305f Selector \u95a2\u6570\uff08Store \u306e State \u306b\u57fa\u3065\u3044\u305f\u30c7\u30fc\u30bf\u3092\u8fd4\u3059\u95a2\u6570\u3002React\u3067\u3044\u3046\u3068useSelector\u306a\u3069\uff09\u3092\u4f5c\u6210\u3059\u308b\u305f\u3081\u306eRedux\u30e9\u30a4\u30d6\u30e9\u30ea\u3067\u3059\u3002<\/p>\n\n\n\n

Selector\u95a2\u6570\u3092\u30e1\u30e2\u5316\u3059\u308b\u306e\u3067\u3001\u4e0d\u8981\u306aSelector\u95a2\u6570\u306e\u518d\u8a08\u7b97\u3092\u9632\u3050\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n

\u307e\u305f\u3001reselect\u306f\u3001\u5165\u529b\u5024\u306b\u57fa\u3065\u3044\u3066\u30e1\u30e2\u5316\u3055\u308c\u305fSelector \u95a2\u6570\uff08outputSelector\uff09\u3092\u751f\u6210\u3059\u308bcreateSelector API\u3092\u63d0\u4f9b\u3057\u307e\u3059\u3002<\/p>\n\n\n\n

\u4f7f\u7528\u65b9\u6cd5\u306f\u3001\u30e1\u30e2\u5316\u3055\u308c\u305fSelector\u95a2\u6570\u3092\u751f\u6210\u3059\u308b createSelector \u3092 component \u306b import \u3059\u308b\u3053\u3068\u3067\u4f7f\u7528\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n

createSelector\u306f\u3001\u5165\u529b\u30bb\u30ec\u30af\u30bf\uff08inputSelector\uff09\u3068\u7d50\u679c\u95a2\u6570\uff08resultFunc\uff09\u3092\u53d7\u3051\u53d6\u308a\u3001\u62bd\u51fa\u3055\u308c\u305f\u5024\u304c\u5909\u66f4\u3055\u308c\u305f\u3068\u304d\u306b\u306e\u307f\u51fa\u529b\u3092\u518d\u8a08\u7b97\u3057\u307e\u3059\u3002<\/p>\n\n\n\n

\u57fa\u672c\u7684\u306a\u4f7f\u3044\u65b9<\/p>\n\n\n\n

const outputSelector = createSelector(\n  [inputSelector1, inputSelector2, inputSelector3], \/\/ synonymous with `dependencies`.\n  resultFunc \/\/ Result function\n)<\/code><\/pre><\/div>\n\n\n\n
\u4f7f\u7528\u4f8b\u306f\u4e0b\u8a18\u306e\u901a\u308a\u3067\u3059\u3002\uff08\u307b\u307c\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u629c\u7c8b\u3057\u305f\u3082\u306e\uff09<\/p>\n\n\n\n
import React from 'react';\nimport { createSelector } from 'reselect';\n\nconst ReselectExample = () => {\n  const state = {\n    todos: [\n      { id: 0, completed: false },\n      { id: 1, completed: true }\n    ],\n    alerts: [\n      { id: 0, read: false },\n      { id: 1, read: true }\n    ]\n  };\n\n  const selectCompletedTodos = (state) => {\n    console.log('selector ran');\n    return state.todos.filter(todo => todo.completed === true);\n  };\n\n  selectCompletedTodos(state); \/\/ selector ran\n  selectCompletedTodos(state); \/\/ selector ran\n  selectCompletedTodos(state); \/\/ selector ran\n\n  const memoizedSelectCompletedTodos = createSelector(\n    [(state) => state.todos],\n    (todos) => {\n      console.log('memoized selector ran');\n      return todos.filter(todo => todo.completed === true);\n    }\n  );\n\n  memoizedSelectCompletedTodos(state); \/\/ memoized selector ran\n  memoizedSelectCompletedTodos(state);\n  memoizedSelectCompletedTodos(state);\n\n  console.log(selectCompletedTodos(state) === selectCompletedTodos(state)); \/\/=> false\n\n  console.log(\n    memoizedSelectCompletedTodos(state) === memoizedSelectCompletedTodos(state)\n  );\n\n  return (\n    <>\n    <\/>\n  );\n};\n\nexport default ReselectExample;\n<\/code><\/pre><\/div>\n\n\n\n
\u4e0a\u8a18\u306e\u30b3\u30fc\u30c9\u3092\u30b3\u30d4\u30da\u3057\u3001google dev tools \u306e console \u3067\u78ba\u8a8d\u3057\u3066\u3044\u305f\u3060\u304f\u3068\u3001memoizedSelectCompletedTodos\u306f 2\u5ea6\u76ee\u30013\u5ea6\u76ee\u306f\u5b9f\u884c\u3055\u308c\u305a\u3001\u524d\u56de\u3068\u540c\u3058\u623b\u308a\u5024\u3092\u8fd4\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u3053\u306e\u3088\u3046\u306b\u3001\u4e0d\u8981\u306a\u518d\u8a08\u7b97\u3092\u30b9\u30ad\u30c3\u30d7\uff08\u30e1\u30e2\u5316\uff09\u3059\u308b\u3060\u3051\u3067\u306a\u304f\u3001memoizedSelectCompletedTodos \u306f\u3001\u518d\u8a08\u7b97\u304c\u306a\u3051\u308c\u3070\u524d\u56de\u30ad\u30e3\u30c3\u30b7\u30e5\u3055\u308c\u305f\u7d50\u679c\u306e\u5024\u3092\u8fd4\u3057\u307e\u3059\u3002<\/p>\n\n\n\n
\u307e\u305f\u3001reselect\u306e\u30e1\u30e2\u5316\u306f\u901a\u5e38\u306e\u30e1\u30e2\u5316\u3068\u306f\u7570\u306a\u308a\u307e\u3059\uff08reselect\u306e\u30e1\u30e2\u5316\u3092 Cascading Memoization<\/strong> <\/a>\u3068\u8a00\u3044\u307e\u3059\uff09\u3002<\/p>\n\n\n\n
\u901a\u5e38\u306e\u30e1\u30e2\u5316\u3060\u3068\u3001\u4e0b\u8a18\u306e\u3088\u3046\u306b\u4e0e\u3048\u3089\u308c\u305f\u5f15\u6570\u304c\u524d\u56de\u3068\u540c\u3058\u5024\u304b\u3069\u3046\u304b\u5224\u65ad\u3057\u3001\u540c\u3058\u306a\u3089\u524d\u56de\u3068\u540c\u3058\u7d50\u679c\u3092\u8fd4\u3057\u3001\u305d\u3046\u3067\u306a\u3044\u306a\u3089\u518d\u3073\u95a2\u6570\u3092\u5b9f\u884c\u3057\u307e\u3059\u3002<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
<\/p>\n\n\n\n
\u305f\u3060\u3057\u3001reselect\u306e\u30e1\u30e2\u5316 Cascading Memoization \u3060\u3068\u3001\u2460\u4e0e\u3048\u3089\u308c\u305f\u5f15\u6570\u304c\u524d\u56de\u3068\u540c\u3058\u5024\u304b\u3069\u3046\u304b\u6bd4\u8f03\u3059\u308b\u3000\u2461\u5165\u529b\u30bb\u30ec\u30af\u30bf\uff08input selectors\uff09\u3092\u5b9f\u884c\u3057\u3001\u73fe\u5728\u306e\u7d50\u679c\u3092\u4ee5\u524d\u306e\u7d50\u679c\u3068\u6bd4\u8f03\u3059\u308b<\/p>\n\n\n\n
\u3088\u3046\u306b \u6bb5\u968e\u7684\u306b\u5404\u5024\u3092\u6bd4\u8f03\u3057\u3001\u30ad\u30e3\u30c3\u30b7\u30e5\u3055\u308c\u305f\u7d50\u679c\u3092\u8fd4\u3059\u3060\u3051\u304b\u3001\u7d50\u679c\u95a2\u6570\uff08result function\uff09\u3092\u5b9f\u884c\u3059\u308b\u304b\u306e\u5224\u65ad\u3092\u884c\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
<\/p>\n\n\n\n
\u3053\u306e\u3088\u3046\u306b\u3057\u3066reselect\u306f\u30e1\u30e2\u5316\u3092\u884c\u3044\u3001\u4e0d\u8981\u306a\u518d\u8a08\u7b97\u3092\u884c\u308f\u306a\u3044\u3088\u3046\u306b\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u307e\u3068\u3081<\/h3>\n\n\n\n
\u4eca\u56de\u3001Redux\u30e9\u30a4\u30d6\u30e9\u30ea\u306e reselect \u306e\u4f7f\u3044\u65b9\u3084reselect\u5185\u3067\u884c\u308f\u308c\u3066\u3044\u308b\u30e1\u30e2\u5316\u306b\u3064\u3044\u3066\u89e3\u8aac\u3044\u305f\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n
\u500b\u4eba\u7684\u306b\u306f\u3001Cascading Memoization \u306e\u4ed5\u7d44\u307f\u304c\u81ea\u5206\u306e\u982d\u306e\u4e2d\u3067\u6574\u7406\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u305f\u306e\u3067\u3001\u826f\u304b\u3063\u305f\u3067\u3059\u3002<\/p>\n\n\n\n
\u307e\u305f\u3001\u5b9f\u52d9\u3067\u306f\u307e\u3060\u4f7f\u7528\u3057\u305f\u3053\u3068\u304c\u306a\u3044\u306e\u3067\u3001\u6a5f\u4f1a\u304c\u3042\u3063\u305f\u3089\u4f7f\u7528\u3057\u3066\u307f\u305f\u3044\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u73fe\u5728\u30c7\u30b6\u30a4\u30f3\u30fb\u30b7\u30b9\u30c6\u30e0\u5ba4\u3067\u306f\u3001\u65b0\u3057\u3044\u30e1\u30f3\u30d0\u30fc\u3092\u52df\u96c6\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
\u5c11\u3057\u3067\u3082\u8208\u5473\u3092\u6301\u305f\u308c\u305f\u65b9\u3001\u305c\u3072\u3054\u5fdc\u52df\u304f\u3060\u3055\u3044\u3002\ud83d\ude04<\/p>\n\n\n\n
<\/p>\n\n\n\n
\n
\u52df\u96c6\u8981\u9805\u304a\u3088\u3073\u30a8\u30f3\u30c8\u30ea\u30fc\u30d5\u30a9\u30fc\u30e0<\/a><\/div>\n<\/div>\n\n\n\n
<\/p>\n\n\n\n
\u53c2\u8003<\/h3>\n\n\n\n
https:\/\/github.com\/reduxjs\/reselect?tab=readme-ov-file<\/a><\/p>\n\n\n\n
https:\/\/reselect.js.org\/introduction\/getting-started<\/a><\/p>\n\n\n\n
https:\/\/reselect.js.org\/introduction\/how-does-reselect-work<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u80cc\u666f Redux\u306e\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u3092\u898b\u3066\u3044\u308b\u3068\u300creselect\u300d\u3068\u3044\u3046\u30e9\u30a4\u30d6\u30e9\u30ea\u306b\u3064\u3044\u3066\u66f8\u304b\u308c\u3066\u304a\u308a\u3001\u3046\u307e\u304f\u5229\u7528\u3059\u308c\u3070\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u30c1\u30e5\u30fc\u30cb\u30f3\u30b0\uff08\u30b7\u30b9\u30c6\u30e0\u306e\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u3092\u5411\u4e0a\u3055\u305b\u308b\u3053\u3068\uff09\u3067\u304d\u308b\u3053\u3068\u3092\u77e5\u308a\u307e\u3057\u305f\u3002 \u4eca\u56de \u30c9 […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[24],"tags":[],"class_list":["post-695","post","type-post","status-publish","format-standard","hentry","category-redux"],"acf":[],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/posts\/695","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/comments?post=695"}],"version-history":[{"count":11,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/posts\/695\/revisions"}],"predecessor-version":[{"id":708,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/posts\/695\/revisions\/708"}],"wp:attachment":[{"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/media?parent=695"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/categories?post=695"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.fundely.co.jp\/tech\/wp-json\/wp\/v2\/tags?post=695"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}