title: Install PHP Extension for PHP 5.6 on OSX with deprecated homebrew/php
body: <p>today I've update Brew and now I can't install the php56-extensions.</p>
  
  <p>On my Mac is installed "php56" and today I had need to install, "php56-redis", but when I had try to install this extension, Brew returned the following error message.</p>
  
  <pre><code>$ brew install php56-redis
  
  Error: No available formula with the name "php56-redis" 
  ==&gt; Searching for a previously deleted formula (in the last month)...
  Warning: homebrew/core is shallow clone. To get complete history run:
    git -C "$(brew --repo homebrew/core)" fetch --unshallow
  
  Error: No previously deleted formula found.
  ==&gt; Searching for similarly named formulae...
  ==&gt; Searching local taps...
  Error: No similarly named formulae found.
  ==&gt; Searching taps...
  ==&gt; Searching taps on GitHub...
  Error: No formulae found in taps.
  </code></pre>
  
  <p>I see on homebrew/php page that this "tap" is deprecated and for now only PHP engine are migrated on php@5.6 but the extensions not works.</p>