title: Bash undeclaring a readonly variable (declare -r var)
body: <p>I can <a href="http://tldp.org/LDP/abs/html/declareref.html" rel="nofollow">declare a bash variable as read only</a>:</p>
  
  <pre><code>var=myname
  declare -r var
  </code></pre>
  
  <p>and then when I try to change the value :</p>
  
  <pre><code>var=anothername
  </code></pre>
  
  <p>I get (in zsh for example)</p>
  
  <pre><code>&gt;&gt;read-only variable: var
  </code></pre>
  
  <p>How can I "undeclare" or unset this variable?</p>