1 files changed, 105 insertions, 0 deletions
diff --git a/files/ja/web/javascript/reference/errors/deprecated_string_generics/index.html b/files/ja/web/javascript/reference/errors/deprecated_string_generics/index.html
new file mode 100644
index 0000000000..24759a56a9
--- /dev/null
+++ b/files/ja/web/javascript/reference/errors/deprecated_string_generics/index.html
@@ -0,0 +1,105 @@
+---
+title: 'Warning: String.x is deprecated; use String.prototype.x instead'
+slug: Web/JavaScript/Reference/Errors/Deprecated_String_generics
+tags:
+  - JavaScript
+  - Warning
+  - エラー
+  - 警告
+translation_of: Web/JavaScript/Reference/Errors/Deprecated_String_generics
+---
+<div>{{jsSidebar("Errors")}}</div>
+
+<p>JavaScript の警告で、 Firefox 68 以前で使用されていた String ジェネリックに関するものです。 String ジェネリックは Firefox 68 から削除されました。</p>
+
+<h2 id="Message" name="Message">メッセージ</h2>
+
+<pre class="syntaxbox">Warning: String.charAt            is deprecated; use String.prototype.charAt            instead
+Warning: String.charCodeAt        is deprecated; use String.prototype.charCodeAt        instead
+Warning: String.concat            is deprecated; use String.prototype.concat            instead
+Warning: String.contains          is deprecated; use String.prototype.contains          instead
+Warning: String.endsWith          is deprecated; use String.prototype.endsWith          instead
+Warning: String.includes          is deprecated; use String.prototype.includes          instead
+Warning: String.indexOf           is deprecated; use String.prototype.indexOf           instead
+Warning: String.lastIndexOf       is deprecated; use String.prototype.lastIndexOf       instead
+Warning: String.localeCompare     is deprecated; use String.prototype.localeCompare     instead
+Warning: String.match             is deprecated; use String.prototype.match             instead
+Warning: String.normalize         is deprecated; use String.prototype.normalize         instead
+Warning: String.replace           is deprecated; use String.prototype.replace           instead
+Warning: String.search            is deprecated; use String.prototype.search            instead
+Warning: String.slice             is deprecated; use String.prototype.slice             instead
+Warning: String.split             is deprecated; use String.prototype.split             instead
+Warning: String.startsWith        is deprecated; use String.prototype.startsWith        instead
+Warning: String.substr            is deprecated; use String.prototype.substr            instead
+Warning: String.substring         is deprecated; use String.prototype.substring         instead
+Warning: String.toLocaleLowerCase is deprecated; use String.prototype.toLocaleLowerCase instead
+Warning: String.toLocaleUpperCase is deprecated; use String.prototype.toLocaleUpperCase instead
+Warning: String.toLowerCase       is deprecated; use String.prototype.toLowerCase       instead
+Warning: String.toUpperCase       is deprecated; use String.prototype.toUpperCase       instead
+Warning: String.trim              is deprecated; use String.prototype.trim              instead
+Warning: String.trimLeft          is deprecated; use String.prototype.trimLeft          instead
+Warning: String.trimRight         is deprecated; use String.prototype.trimRight         instead
+</pre>
+
+<h2 id="Error_type" name="Error_type">エラー種別</h2>
+
+<p>警告。 JavaScript の実行は中断されません。</p>
+
+<h2 id="What_went_wrong" name="What_went_wrong">原因</h2>
+
+<p>標準外のジェネリック {{jsxref("String")}} のメソッドは非推奨であり、 Firefox 68 で削除されました。 String ジェネリックは、 <code>String</code> インスタンスメソッドを <code>String</code> オブジェクトに提供し、 <code>String</code> の「メソッドを任意のオブジェクトに適用できるようにします。</p>
+
+<h2 id="Examples" name="Examples">例</h2>
+
+<h3 id="Deprecated_syntax" name="Deprecated_syntax">非推奨の構文</h3>
+
+<pre class="brush: js example-bad">var num = 15;
+String.replace(num, /5/, '2');</pre>
+
+<h3 id="Standard_syntax" name="Standard_syntax">標準の構文</h3>
+
+<pre class="brush: js example-good">var num = 15;
+String(num).replace(/5/, '2');
+</pre>
+
+<h2 id="Shim">Shim</h2>
+
+<p>対応していないブラウザーで対応できるようにするための Shim です。</p>
+
+<pre class="brush: js">/*globals define*/
+// Assumes all supplied String instance methods already present
+// (one may use shims for these if not available)
+(function() {
+  'use strict';
+
+  var i,
+    // We could also build the array of methods with the following, but the
+    //   getOwnPropertyNames() method is non-shimable:
+    // Object.getOwnPropertyNames(String).filter(function(methodName) {
+    //   return typeof String[methodName] === 'function';
+    // });
+    methods = [
+      'contains', 'substring', 'toLowerCase', 'toUpperCase', 'charAt',
+      'charCodeAt', 'indexOf', 'lastIndexOf', 'startsWith', 'endsWith',
+      'trim', 'trimLeft', 'trimRight', 'toLocaleLowerCase', 'normalize',
+      'toLocaleUpperCase', 'localeCompare', 'match', 'search', 'slice',
+      'replace', 'split', 'substr', 'concat', 'localeCompare'
+    ],
+    methodCount = methods.length,
+    assignStringGeneric = function(methodName) {
+      var method = String.prototype[methodName];
+      String[methodName] = function(arg1) {
+        return method.apply(arg1, Array.prototype.slice.call(arguments, 1));
+      };
+    };
+
+  for (i = 0; i &lt; methodCount; i++) {
+    assignStringGeneric(methods[i]);
+  }
+}());</pre>
+
+<h2 id="See_also" name="See_also">関連情報</h2>
+
+<ul>
+ <li>{{jsxref("String")}}</li>
+</ul>