title: how do I declare const variables in ruby/rails
body: <p>I would like to be a better code.. making my code cleaner and more readable. </p>
  
  <p>One thing I've seen in c/c++ is the use of const on local variables. I think there is a lot of value in telling the reader of my code that once the variable is set, it is not changed in the function/method. </p>
  
  <p>I'm wondering.... is there a way to indicate a local variable is const?</p>
  
  <pre><code>#for example 
  sql = "select * from table1 where status = #{iStatusId}"
  connection.execute(sql)
  </code></pre>
  
  <p>sql will not change in this method.  Can I mark it so?</p>
  
  <p>Ok.. that's a bad example, but I think the point is made... I hope :)</p>
  
  <p>EDIT:
  I added a bit of dynamic to the sql.. the iStatusId bit is a parameter passed into the method.  </p>
  
  <p>EDIT2:
  I did google this...  all articles talk of magic number replacement.  That's a no brainer and what I'd consider a MACRO.  CONTANTS are easy... I'm looking for const..   they are very different things.</p>