title: sed replace a text with text in variable
body: <p>We have a ASCII art like the following</p>
  
  <pre><code>ART  _____                            
  ART |  __ \               
  ART | |__) |__  ___ _ __   
  ART |  ___/ _ \/ _ \ '__|  
  ART | |  |  __/  __/ |    
  ART |_|   \___|\___|_|     
  ART                        
  ART                        
  </code></pre>
  
  <p>We have a variable ${art}="123456" and want to replace ART with ${art}, so the system will print the standard output like this </p>
  
  <pre><code>123456  _____                            
  123456 |  __ \               
  123456 | |__) |__  ___ _ __   
  123456 |  ___/ _ \/ _ \ '__|  
  123456 | |  |  __/  __/ |    
  123456 |_|   \___|\___|_|     
  123456                        
  123456                       
  </code></pre>
  
  <p>I have tried this as this post suggests</p>
  
  <pre><code>sed -i "s/ART/${art}/g" ascii-art 
  </code></pre>
  
  <p>The following error message shows up:</p>
  
  <pre><code>sed: -e expression #1, char 6: unterminated `s' command
  </code></pre>
  
  <p>I am in <code>Linux ip-10-22-37-149 4.4.8-20.46.amzn1.x86_64 #1 SMP Wed Apr 27 19:28:52 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux (Amazon EC2)</code></p>
  
  <p>sed --version returns:</p>
  
  <pre><code>GNU sed version 4.2.1
  Copyright (C) 2009 Free Software Foundation, Inc.
  This is free software; see the source for copying conditions.  There is NO
  warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE,
  to the extent permitted by law.
  
  GNU sed home page: &lt;http://www.gnu.org/software/sed/&gt;.
  General help using GNU software: &lt;http://www.gnu.org/gethelp/&gt;.
  E-mail bug reports to: &lt;bug-gnu-utils@gnu.org&gt;.
  Be sure to include the word ``sed'' somewhere in the ``Subject:'' field.
  </code></pre>
  
  <p>Any thoughts? </p>
  
  <p>Thanks!</p>