title: How borrow as mutable vs immutable in Rust?
body: <p>I've read these docs: <a href="https://doc.rust-lang.org/rust-by-example/scope/borrow/mut.html" rel="noreferrer">https://doc.rust-lang.org/rust-by-example/scope/borrow/mut.html</a></p>
  
  <p>I've also read this question: (<a href="https://stackoverflow.com/questions/35005704/cannot-borrow-immutable-borrowed-content-as-mutable">Cannot borrow immutable borrowed content as mutable</a>)</p>
  
  <hr>
  
  <p>The docs helped me understand how to declare borrowing as mutable (I think):</p>
  
  <pre><code>let mut (part1, part2) = someTuple;
  </code></pre>
  
  <p>But I'm haven't been able to find explicit instructions on what borrowing as an immutable looks like.  This is my guess:</p>
  
  <pre><code>let (part1, part2) = someTuple;
  </code></pre>
  
  <hr>
  
  <p>I know this is a super basic question, but Googling it took me way off into the deep end of explanations and I'm still trying to get my bearings in the most simple of contexts.</p>
  
  <p><strong>How do I borrow as mutable vs an immutable in Rust?</strong></p>