title: Need to check input arguments Bash Shell Script on Mac
body: <p>I want to check input arguments presence on a bash script on OSX.  I do:</p>
  
  <pre><code>if [-z "$1"]
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>/usr/local/bin/deploy.sh: line 8: [-z: command not found
  </code></pre>
  
  <p>Any tips?</p>
  
  <p>Thanks.</p>