title: Laravel Non-Mutating Collection `put()` Method
body: <p>Does Laravel have a collection method that does the same thing as <code>-&gt;put()</code> but does not mutate the original collection?</p>
  <p>What I'm looking for:</p>
  <pre class="lang-php prettyprint-override"><code>&lt;?php
  
  $collection = collect(['key' =&gt; 'value']);
  
  $new = $collection-&gt;putProperly('another', 'pair');
  
  $collection // =&gt; ['key' =&gt; 'value']
  $new // =&gt; ['key' =&gt; 'value', 'another' =&gt; 'pair']
  </code></pre>
  <p>I already know I can do this:</p>
  <pre class="lang-php prettyprint-override"><code>$new = $collection-&gt;merge(['another' =&gt; 'pair'])
  </code></pre>