title: Javascript: Is the length method efficient?
body: <p>i'm doing some javascript coding and I was wondering if the length method is "precomputed", or remembered by the JS engine.</p>
  
  <p>So, the question is:</p>
  
  <p>If I'm checking really often for an array length, and supposing that i'm not changing it (making it immutable through a closure), should I precompute the length method and store it in some variable?</p>
  
  <p>Thanks!</p>