Update syntax blocks for TypedArray pages (mdn#4677)

* Update syntax blocks for TypedArray pages

* Address feedback

* Use accumulator instead of previousValue

files/en-us/web/javascript/reference/global_objects/typedarray/@@iterator/index.html

@@ -19,7 +19,7 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre class="brush: js"><var>arr</var>[Symbol.iterator]()</pre>
+<pre class="brush: js">[Symbol.iterator]()</pre>
 
 <h3 id="Return_value">Return value</h3>
 

files/en-us/web/javascript/reference/global_objects/typedarray/at/index.html

@@ -23,7 +23,7 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre class="syntaxbox">var <var>item</var> = typedArr.at(index)</pre>
+<pre class="brush: js">at(index)</pre>
 
 <h3 id="Parameters">Parameters</h3>
 

files/en-us/web/javascript/reference/global_objects/typedarray/copywithin/index.html

@@ -26,8 +26,10 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><code><var>typedarray</var>.copyWithin(<var>target</var>, <var>start</var>[, <var>end</var> = this.length])</code></pre>
+<pre class="brush: js">
+copyWithin(target, start)
+copyWithin(target, start, end)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 

files/en-us/web/javascript/reference/global_objects/typedarray/entries/index.html

@@ -21,7 +21,7 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre class="brush: js"><var>arr</var>.entries()</pre>
+<pre class="brush: js">entries()</pre>
 
 <h3 id="Return_value">Return value</h3>
 

files/en-us/web/javascript/reference/global_objects/typedarray/every/index.html

@@ -24,13 +24,27 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><var>typedarray</var>.every(<var>callback</var>[, <var>thisArg</var>])</pre>
+<pre class="brush: js">
+// Arrow function
+every((element) => { ... } )
+every((element, index) => { ... } )
+every((element, index, array) => { ... } )
+
+// Callback function
+every(callbackFn)
+every(callbackFn, thisArg)
+
+// Inline callback function
+every(function callbackFn(element) { ... })
+every(function callbackFn(element, index) { ... })
+every(function callbackFn(element, index, array){ ... })
+every(function callbackFn(element, index, array) { ... }, thisArg)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 
 <dl>
-  <dt><code><var>callback</var></code></dt>
+  <dt><code><var>callbackFn</var></code></dt>
   <dd>A function to test for each element, taking three arguments:
     <dl>
       <dt><code><var>element</var></code></dt>
@@ -42,7 +56,7 @@ <h3 id="Parameters">Parameters</h3>
     </dl>
   </dd>
   <dt><code><var>thisArg</var></code> {{Optional_inline}}</dt>
-  <dd>A value to use as <code>this</code> when executing <code><var>callback</var></code>.
+  <dd>A value to use as <code>this</code> when executing <code><var>callbackFn</var></code>.
   </dd>
 </dl>
 
@@ -53,20 +67,20 @@ <h3 id="Return_value">Return value</h3>
 
 <h2 id="Description">Description</h2>
 
-<p>The <code>every</code> method executes the provided <code><var>callback</var></code>
+<p>The <code>every</code> method executes the provided <code><var>callbackFn</var></code>
   function once for each element present in the typed array until it finds the one where
-  <code><var>callback</var></code> returns a falsy{{Glossary("falsy")}} value. If such an
+  <code><var>callbackFn</var></code> returns a {{Glossary("falsy")}} value. If such an
   element is found, the <code>every</code> method immediately returns <code>false</code>.
-  Otherwise, if <code><var>callback</var></code> returns a {{Glossary("truthy")}} value
+  Otherwise, if <code><var>callbackFn</var></code> returns a {{Glossary("truthy")}} value
   for all elements, <code>every</code> returns <code>true</code>.</p>
 
-<p><code><var>callback</var></code> is invoked with three arguments: the value of the
+<p><code><var>callbackFn</var></code> is invoked with three arguments: the value of the
   element, the index of the element, and the typed array object being traversed.</p>
 
 <p>If a <code><var>thisArg</var></code> parameter is provided to <code>every</code>, it
   will be used as callback's <code>this</code> value. Otherwise, the value
   <code>undefined</code> will be used as its <code>this</code> value. The
-  <code>this</code> value ultimately observable by <code><var>callback</var></code> is
+  <code>this</code> value ultimately observable by <code><var>callbackFn</var></code> is
   determined according to <a
     href="/en-US/docs/Web/JavaScript/Reference/Operators/this">the usual rules for
     determining the <code>this</code> seen by a function</a>.</p>

files/en-us/web/javascript/reference/global_objects/typedarray/fill/index.html

@@ -23,8 +23,11 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><var>typedarray</var>.fill(<var>value</var>[, <var>start = 0</var>[, <var>end = this.length</var>]])</pre>
+<pre class="brush: js">
+fill(value)
+fill(value, start)
+fill(value, start, end)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 

files/en-us/web/javascript/reference/global_objects/typedarray/filter/index.html

@@ -24,18 +24,32 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><var>typedarray</var>.filter(<var>callback</var>[, <var>thisArg</var>])</pre>
+<pre class="brush: js">
+// Arrow function
+filter((element) => { ... } )
+filter((element, index) => { ... } )
+filter((element, index, array) => { ... } )
+
+// Callback function
+filter(callbackFn)
+filter(callbackFn, thisArg)
+
+// Inline callback function
+filter(function callbackFn(element) { ... })
+filter(function callbackFn(element, index) { ... })
+filter(function callbackFn(element, index, array){ ... })
+filter(function callbackFn(element, index, array) { ... }, thisArg)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 
 <dl>
-  <dt><code><var>callback</var></code></dt>
+  <dt><code><var>callbackFn</var></code></dt>
   <dd>Function to test each element of the typed array. Invoked with arguments
-    <code>(<var>element</var>, <var>index</var>, <var>typedarray</var>)</code>. Return
+    <code>(<var>element</var>, <var>index</var>, <var>array</var>)</code>. Return
     <code>true</code> to keep the element, <code>false</code> otherwise.</dd>
   <dt><code><var>thisArg</var></code>{{optional_inline}}</dt>
-  <dd>Value to use as <code>this</code> when executing <code><var>callback</var></code>.
+  <dd>Value to use as <code>this</code> when executing <code><var>callbackFn</var></code>.
   </dd>
 </dl>
 
@@ -45,17 +59,17 @@ <h3 id="Return_value">Return value</h3>
 
 <h2 id="Description">Description</h2>
 
-<p>The <code>filter()</code> method calls a provided <code><var>callback</var></code>
+<p>The <code>filter()</code> method calls a provided <code><var>callbackFn</var></code>
   function once for each element in a typed array, and constructs a new typed array of all
-  the values for which <code><var>callback</var></code> returns <a
+  the values for which <code><var>callbackFn</var></code> returns <a
     href="/en-US/docs/Glossary/Truthy">a value that coerces to <code>true</code></a>.
-  <code><var>callback</var></code> is invoked only for indexes of the typed array which
+  <code><var>callbackFn</var></code> is invoked only for indexes of the typed array which
   have assigned values; it is not invoked for indexes which have been deleted or which
   have never been assigned values. Typed array elements which do not pass the
-  <code><var>callback</var></code> test are skipped, and are not included in the new typed
+  <code><var>callbackFn</var></code> test are skipped, and are not included in the new typed
   array.</p>
 
-<p><code><var>callback</var></code> is invoked with three arguments:</p>
+<p><code><var>callbackFn</var></code> is invoked with three arguments:</p>
 
 <ol>
   <li>the value of the element</li>
@@ -64,20 +78,20 @@ <h2 id="Description">Description</h2>
 </ol>
 
 <p>If a <code><var>thisArg</var></code> parameter is provided to <code>filter()</code>, it
-  will be passed to <code><var>callback</var></code> when invoked, for use as its
+  will be passed to <code><var>callbackFn</var></code> when invoked, for use as its
   <code>this</code> value. Otherwise, the value <code>undefined</code> will be passed for
   use as its <code>this</code> value. The <code>this</code> value ultimately observable by
-  <code><var>callback</var></code> is determined according to <a
+  <code><var>callbackFn</var></code> is determined according to <a
     href="/en-US/docs/Web/JavaScript/Reference/Operators/this">the usual rules for
     determining the <code>this</code> seen by a function</a>.</p>
 
 <p><code>filter()</code> does not mutate the typed array on which it is called.</p>
 
 <p>The range of elements processed by <code>filter()</code> is set before the first
-  invocation of <code><var>callback</var></code>. Elements which are appended to the typed
+  invocation of <code><var>callbackFn</var></code>. Elements which are appended to the typed
   array after the call to <code>filter()</code> begins will not be visited by
-  <code><var>callback</var></code>. If existing elements of the typed array are changed,
-  or deleted, their value as passed to <code><var>callback</var></code> will be the value
+  <code><var>callbackFn</var></code>. If existing elements of the typed array are changed,
+  or deleted, their value as passed to <code><var>callbackFn</var></code> will be the value
   at the time <code>filter()</code> visits them; elements that are deleted are not
   visited.</p>
 

files/en-us/web/javascript/reference/global_objects/typedarray/find/index.html

@@ -28,13 +28,27 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><var>typedarray</var>.find(<var>callback</var>[, <var>thisArg</var>])</pre>
+<pre class="brush: js">
+// Arrow function
+find((element) => { ... } )
+find((element, index) => { ... } )
+find((element, index, array) => { ... } )
+
+// Callback function
+find(callbackFn)
+find(callbackFn, thisArg)
+
+// Inline callback function
+find(function callbackFn(element) { ... })
+find(function callbackFn(element, index) { ... })
+find(function callbackFn(element, index, array){ ... })
+find(function callbackFn(element, index, array) { ... }, thisArg)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 
 <dl>
-  <dt><code><var>callback</var></code></dt>
+  <dt><code><var>callbackFn</var></code></dt>
   <dd>Function to execute on each value in the typed array, taking three arguments:
     <dl>
       <dt><code><var>element</var></code></dt>
@@ -46,7 +60,7 @@ <h3 id="Parameters">Parameters</h3>
     </dl>
   </dd>
   <dt><code><var>thisArg</var></code> {{optional_inline}}</dt>
-  <dd>Object to use as <code>this</code> when executing <code><var>callback</var></code>.
+  <dd>Object to use as <code>this</code> when executing <code><var>callbackFn</var></code>.
   </dd>
 </dl>
 
@@ -57,31 +71,31 @@ <h3 id="Return_value">Return value</h3>
 
 <h2 id="Description">Description</h2>
 
-<p>The <code>find()</code> method executes the <code><var>callback</var></code> function
+<p>The <code>find()</code> method executes the <code><var>callbackFn</var></code> function
   once for each element present in the typed array until it finds one where
-  <code><var>callback</var></code> returns a true value. If such an element is found,
+  <code><var>callbackFn</var></code> returns a true value. If such an element is found,
   <code>find()</code> immediately returns the value of that element. Otherwise,
-  <code>find()</code> returns {{jsxref("undefined")}}. <code><var>callback</var></code> is
+  <code>find()</code> returns {{jsxref("undefined")}}. <code><var>callbackFn</var></code> is
   invoked only for indexes of the typed array which have assigned values; it is not
   invoked for indexes which have been deleted or which have never been assigned values.
 </p>
 
-<p><code><var>callback</var></code> is invoked with three arguments: the value of the
+<p><code><var>callbackFn</var></code> is invoked with three arguments: the value of the
   element, the index of the element, and the typed array object being traversed.</p>
 
 <p>If a <code><var>thisArg</var></code> parameter is provided to <code>find()</code>, it
   will be used as the <code>this</code> for each invocation of the
-  <code><var>callback</var></code>. If it is not provided, then {{jsxref("undefined")}} is
+  <code><var>callbackFn</var></code>. If it is not provided, then {{jsxref("undefined")}} is
   used.</p>
 
 <p><code>find()</code> does not mutate the typed array on which it is called.</p>
 
 <p>The range of elements processed by <code>find()</code> is set before the first
-  invocation of <code><var>callback</var></code>. Elements that are appended to the typed
+  invocation of <code><var>callbackFn</var></code>. Elements that are appended to the typed
   array after the call to <code>find()</code> begins will not be visited by
-  <code><var>callback</var></code>. If an existing, unvisited element of the typed array
-  is changed by <code><var>callback</var></code>, its value passed to the visiting
-  <code><var>callback</var></code> will be the value at the time that <code>find()</code>
+  <code><var>callbackFn</var></code>. If an existing, unvisited element of the typed array
+  is changed by <code><var>callbackFn</var></code>, its value passed to the visiting
+  <code><var>callbackFn</var></code> will be the value at the time that <code>find()</code>
   visits that element's index; elements that are deleted are not visited.</p>
 
 <h2 id="Examples">Examples</h2>

files/en-us/web/javascript/reference/global_objects/typedarray/findindex/index.html

@@ -25,13 +25,27 @@
 
 <h2 id="Syntax">Syntax</h2>
 
-<pre
-  class="brush: js"><var>typedarray</var>.findIndex(<var>callback</var>[, <var>thisArg</var>])</pre>
+<pre class="brush: js">
+// Arrow function
+findIndex((element) => { ... } )
+findIndex((element, index) => { ... } )
+findIndex((element, index, array) => { ... } )
+
+// Callback function
+findIndex(callbackFn)
+findIndex(callbackFn, thisArg)
+
+// Inline callback function
+findIndex(function callbackFn(element) { ... })
+findIndex(function callbackFn(element, index) { ... })
+findIndex(function callbackFn(element, index, array){ ... })
+findIndex(function callbackFn(element, index, array) { ... }, thisArg)
+</pre>
 
 <h3 id="Parameters">Parameters</h3>
 
 <dl>
-  <dt><code><var>callback</var></code></dt>
+  <dt><code><var>callbackFn</var></code></dt>
   <dd>Function to execute on each value in the typed array, taking three arguments:
     <dl>
       <dt><code><var>element</var></code></dt>
@@ -43,7 +57,7 @@ <h3 id="Parameters">Parameters</h3>
     </dl>
   </dd>
   <dt><code><var>thisArg</var></code> {{optional_inline}}</dt>
-  <dd>Object to use as <code>this</code> when executing <code><var>callback</var></code>.
+  <dd>Object to use as <code>this</code> when executing <code><var>callbackFn</var></code>.
   </dd>
 </dl>
 
@@ -53,15 +67,15 @@ <h3 id="Return_value">Return value</h3>
 
 <h2 id="Description">Description</h2>
 
-<p>The <code>findIndex()</code> method executes the <code><var>callback</var></code>
+<p>The <code>findIndex()</code> method executes the <code><var>callbackFn</var></code>
   function once for each element present in the typed array until it finds one where
-  <code><var>callback</var></code> returns a true value. If such an element is found,
+  <code><var>callbackFn</var></code> returns a true value. If such an element is found,
   <code>findIndex()</code> immediately returns the index of that element. Otherwise,
-  <code>findIndex()</code> returns -1. <code><var>callback</var></code> is invoked only
+  <code>findIndex()</code> returns -1. <code><var>callbackFn</var></code> is invoked only
   for indexes of the typed array which have assigned values; it is not invoked for indexes
   which have been deleted or which have never been assigned values.</p>
 
-<p><code><var>callback</var></code> is invoked with three arguments: the value of the
+<p><code><var>callbackFn</var></code> is invoked with three arguments: the value of the
   element, the index of the element, and the typed array object being traversed.</p>
 
 <p>If a <code><var>thisArg</var></code> parameter is provided to <code>findIndex()</code>,
@@ -72,11 +86,11 @@ <h2 id="Description">Description</h2>
 <p><code>findIndex()</code> does not mutate the typed array on which it is called.</p>
 
 <p>The range of elements processed by <code>findIndex()</code> is set before the first
-  invocation of <code><var>callback</var></code>. Elements that are appended to the typed
+  invocation of <code><var>callbackFn</var></code>. Elements that are appended to the typed
   array after the call to <code>findIndex()</code> begins will not be visited by
-  <code><var>callback</var></code>. If an existing, unvisited element of the typed array
-  is changed by <code><var>callback</var></code>, its value passed to the visiting
-  <code><var>callback</var></code> will be the value at the time that
+  <code><var>callbackFn</var></code>. If an existing, unvisited element of the typed array
+  is changed by <code><var>callbackFn</var></code>, its value passed to the visiting
+  <code><var>callbackFn</var></code> will be the value at the time that
   <code>findIndex()</code> visits that element's index; elements that are deleted are not
   visited.</p>