title: Properly initialize NSMutableString
body: <p>I declare an object in the beginning of M file as follows:</p>
  
  <pre><code>NSMutableString *SomeString;
  </code></pre>
  
  <p>And in a method I try to init it:</p>
  
  <pre><code>SomeString  = [NSMutableString stringWithFormat:@"%c",'0'];
  NSMutableString *SomeOtherString = [NSMutableString stringWithFormat:@"%c",'0'];
  </code></pre>
  
  <p>When I debug after the above line, I see that <code>SomeOtherString</code> holds the string <code>"0"</code> but <code>SomeString</code> remains empty. What am I doing wrong?</p>