title: Best idiom for a decrementing loop
body: <p>What's the best/preferred idiom for a decrementing for loop, and why?</p>
  
  <pre><code>for(int idx=(len-1); idx&gt;=0; idx--) {...}
  </code></pre>
  
  <p>or</p>
  
  <pre><code>for(int idx=(len-1); idx&gt;-1; idx--) {...}
  </code></pre>
  
  <p>or (based on sylvarking's answer, but using for to constrain the index scope)</p>
  
  <pre><code>for(int idx=len; idx--&gt;0; ) {...}
  </code></pre>
  
  <p>Is one or the other more likely to trip up another developer?</p>