title: What is the meaning of - (single dash) in "git checkout - ..."?
body: <p>In my repository, I had some changes (let's say that all the edited files' paths started with <code>abc_</code>) that I wanted to discard, with the command:</p>
  
  <pre><code>git checkout -- abc_*
  </code></pre>
  
  <p>However, I made a typo and instead of two dashes I used only one:</p>
  
  <pre><code>git checkout - abc_*
  </code></pre>
  
  <p>Looks like instead of discarding the changes, the command added even more changes to be committed - in fact, it added a few hundred files whose names started with <code>abc_</code> (but not all of them in the project!). </p>
  
  <p>My question is:
  What have I just done? Or, more precisely: <strong>what does the dash stand for?</strong> </p>
  
  <p>All the answers that I was able to find explained what two dashes (--) do, but I understand this. I also believe I understand how <code>git checkout</code> works, both with the branch/tree-ish argument or with file paths. I cannot find any information on the single dash meaning, however - dashes are also used to designate parameters (e.g. <code>git checkout -b ...</code>), and it makes searching for this command problematic.</p>