title: When is the EACH operator extension necessary in K besides mod/rotate?
body: <p>In the K language, an operator can be suffixed with an apostrophe to apply to each element in an array:</p>
  
  <pre><code>  8 +' 2 4 10
  10 12 18
    9 &lt;' 3 10 2
  0 1 0
    8 -' 1 7 10
  7 1 -2
  </code></pre>
  
  <p>However, in each of those cases, the apostrophe is not required, because these dyadic verbs naturally apply across the array:</p>
  
  <pre><code>  8 + 2 4 10
  10 12 18
    9 &lt; 3 10 2
  0 1 0
    8 - 1 7 10
  7 1 -2
  </code></pre>
  
  <p>The <em>only</em> place I have yet seen there to be a difference is with the <code>!</code> verb, which applies the modulo operation for each element of the array when decorated with <code>'</code> but acts as a rotate when not decorated:</p>
  
  <pre><code>  3 !' 1 2 3 4 5
  0 1 0 3 3
    3 ! 1 2 3 4 5
  4 5 1 2 3
  </code></pre>
  
  <p>Are there <em>any other</em> places in K where the decorated (apostrophe-d) version of a verb is different from the undecorated case? (I'm new to K so very likely am missing such cases!)</p>