Add explain of control syntax

docs/commands_reference/control.html

@@ -174,6 +174,29 @@ <h1 class="menu-title">Documents of Stack Programming Language</h1>
                 <div id="content" class="content">
                     <main>
                         <h1 id="control"><a class="header" href="#control">Control</a></h1>
+<p>Any programming language needs control syntax.
+In this chapter, Explain control syntax such as <code>if</code>, <code>while</code> etc of Stack.</p>
+<h2 id="if"><a class="header" href="#if">If</a></h2>
+<p><strong>Example</strong>:<br />
+In this code, judgement which even or odd is 5987.</p>
+<pre><code>Stack〔  〕 ←  (Even print)
+Stack〔 (Even print) 〕 ←  (Odd print)
+Stack〔 (Even print) | (Odd print) 〕 ←  5987
+Stack〔 (Even print) | (Odd print) | 5987 〕 ←  2
+Stack〔 (Even print) | (Odd print) | 5987 | 2 〕 ←  mod
+Stack〔 (Even print) | (Odd print) | 1 〕 ←  0
+Stack〔 (Even print) | (Odd print) | 1 | 0 〕 ←  equal
+Stack〔 (Even print) | (Odd print) | false 〕 ←  if
+Stack〔  〕 ←  Odd
+Stack〔 (Odd) 〕 ←  print
+[Output]: Odd
+</code></pre>
+<p><strong>Result</strong>:</p>
+<pre><code class="language-stack-repl">Stack〔  〕 ←  3
+Stack〔 3 〕 ←  4
+Stack〔 3 | 4 〕 ←  add
+Stack〔 7 〕
+</code></pre>
 
                     </main>
 

docs/print.html

@@ -401,6 +401,29 @@ <h2 id="combining-operations"><a class="header" href="#combining-operations">Com
 </code></pre>
 <div style="break-before: page; page-break-before: always;"></div><h1 id="inputoutput"><a class="header" href="#inputoutput">Input/Output</a></h1>
 <div style="break-before: page; page-break-before: always;"></div><h1 id="control"><a class="header" href="#control">Control</a></h1>
+<p>Any programming language needs control syntax.
+In this chapter, Explain control syntax such as <code>if</code>, <code>while</code> etc of Stack.</p>
+<h2 id="if"><a class="header" href="#if">If</a></h2>
+<p><strong>Example</strong>:<br />
+In this code, judgement which even or odd is 5987.</p>
+<pre><code>Stack〔  〕 ←  (Even print)
+Stack〔 (Even print) 〕 ←  (Odd print)
+Stack〔 (Even print) | (Odd print) 〕 ←  5987
+Stack〔 (Even print) | (Odd print) | 5987 〕 ←  2
+Stack〔 (Even print) | (Odd print) | 5987 | 2 〕 ←  mod
+Stack〔 (Even print) | (Odd print) | 1 〕 ←  0
+Stack〔 (Even print) | (Odd print) | 1 | 0 〕 ←  equal
+Stack〔 (Even print) | (Odd print) | false 〕 ←  if
+Stack〔  〕 ←  Odd
+Stack〔 (Odd) 〕 ←  print
+[Output]: Odd
+</code></pre>
+<p><strong>Result</strong>:</p>
+<pre><code class="language-stack-repl">Stack〔  〕 ←  3
+Stack〔 3 〕 ←  4
+Stack〔 3 | 4 〕 ←  add
+Stack〔 7 〕
+</code></pre>
 <div style="break-before: page; page-break-before: always;"></div><h1 id="string"><a class="header" href="#string">String</a></h1>
 <div style="break-before: page; page-break-before: always;"></div><h1 id="list"><a class="header" href="#list">List</a></h1>
 <div style="break-before: page; page-break-before: always;"></div><h1 id="functional"><a class="header" href="#functional">Functional</a></h1>