title: What is the most portable way to delete element from multidimensional array in javascript?
body: <p>What is the most portable way to delete element from multidimensional sparse array in javascript?</p>
  
  <p>Will following  work well if rows can be undefined sometimes?</p>
  
  <pre><code>if( content[row] ) {
      delete content[row][col];
  }
  </code></pre>
  
  <p>Will this work and will it be better?</p>
  
  <pre><code>if( r=content[row] ) {
      delete r[col];
  }
  </code></pre>