title: R OSRM: Error in doTryCatch(return(expr), name, parentenv, handler): object 'res' not found
body: <p>Trying to do a simple isochrone using the <code>osrm</code> package in R, following this example:
  <a href="https://rstudio-pubs-static.s3.amazonaws.com/259089_2f5213f21003443994b28aab0a54cfd6.html" rel="nofollow noreferrer">https://rstudio-pubs-static.s3.amazonaws.com/259089_2f5213f21003443994b28aab0a54cfd6.html</a></p>
  <p><code>iso1 &lt;- osrm::osrmIsochrone(loc=c(-93.2223, 44.8848),breaks=10)</code></p>
  <p>Yields the following output to the console.  This occurs whether I try to call the default server  <a href="https://routing.openstreetmap.de/" rel="nofollow noreferrer">https://routing.openstreetmap.de/</a> or an internal OSRM server. I assume this is a simple problem, but I haven't seen anything on Google or SO.</p>
  <pre><code>Error in doTryCatch(return(expr), name, parentenv, handler): object 'res' not found {repeat 8 more times}
  
  Error in UseMethod(&quot;st_as_sf&quot;) : 
    no applicable method for 'st_as_sf' applied to an object of class &quot;NULL&quot; ```
  
  </code></pre>