title: Can not require third-party library in lein repl
body: <ul>
  <li>clojure version: 1.8.0</li>
  <li>leiningen version: 2.7.1</li>
  <li>jdk version: 1.8.0_101</li>
  </ul>
  
  <p>When I require a library, say <code>reagent</code>(has added in the project dependencies), in the lein repl:</p>
  
  <pre><code>user=&gt; (require '[reagent.core :as r])
  nil
  </code></pre>
  
  <p>The output is nil, which I think it means success. But when I use the <code>r</code>,say <code>(r/atom 3)</code>, the repl throw an error says:</p>
  
  <pre><code>CompilerException java.lang.RuntimeException: Unable to resolve symbol: r in
  this context, compiling:  (/private/var/folders/_y/n3ym4ftj2ld9tl471g_kcv_00000gn/T
  /form-init1002540725014588615.clj:1:4923) 
  </code></pre>
  
  <p>That seems strange. 
  Anyone has some idea?</p>
  
  <p>By the way, I can require java and clojure library.</p>