title: editline/history.h and editline/readline.h not found/working on macOS when trying to compile with developer tools installed already
body: <p>I am working on this tutorial on building your own LISP (<a href="http://www.buildyourownlisp.com/chapter4_interactive_prompt" rel="nofollow noreferrer">http://www.buildyourownlisp.com/chapter4_interactive_prompt</a>) and for some reason when I try to compile I get this:</p>
  <pre><code>REPL.c:4:10: fatal error: 'editline/readline.h' file not found
  #include &lt;editline/history.h&gt;
  ^
  1 error generated.
  </code></pre>
  <p>I have installed the macOS developer tools, and brew is showing readline is installed and it doesn't know what to do when I try brew install editline.</p>
  <p>This is my code:</p>
  <pre><code>  1 #include &lt;stdio.h&gt;
    2 #include &lt;stdlib.h&gt;
    3 #include &lt;editline/readline.h&gt;
    4 #include &lt;editline/history.h&gt;
    5 
    6 int main(int argc, char** argv) {
    7      
    8   /* version/exit info */
    9   puts(&quot;Edward Version 0.0.1&quot;);
   10   puts(&quot;Press Ctrl+c to Exit\n&quot;);
   11          
   12   /* endless loop for main REPL */
   13   while (1) { 
   14     /* output prompt and read line */
   15     char* input = readline(&quot;lispy&gt; &quot;);
   16                   
   17     /* put input in history  */
   18     add_history(input);
   19                       
   20     /* Echo input back */                          
   21     printf(&quot;No you're a %s\n&quot;, input);
   22                       
   23     /* free input */
   24     free(input);
   25   }                           
   26   return 0;
   27 } 
  </code></pre>
  <p>It is obviously very basic, but I really want to get this project rolling so I'm hoping I can figure this out. This is what I'm using to compile:</p>
  <pre><code>cc -std=c99 -Wall REPL.c -ledit -o REPL
  </code></pre>