title: Test for string equality / string comparison in Fish shell?
body: <p>How do you compare two strings in Fish (like <code>"abc" == "def"</code> in other languages)?</p>
  
  <p>So far, I've used a combination of <code>contains</code> (turns out that <code>contains "" $a</code> only returns <code>0</code> if <code>$a</code> is the empty string, although that hasn't seemed to work for me in all cases) and <code>switch</code> (with a <code>case "what_i_want_to_match"</code> and a <code>case '*'</code>). Neither of these methods seem particularly... correct, though.</p>