title: How to convert from shape into polygon in R? There was shape2poly(shapefiles) but this function have been removed
body: <p>How to convert from shape into polygon in R? There was <code>shape2poly(shapefiles)</code> but this function have been removed, are <code>shapefiles</code>, <code>maptools</code>, <code>spdep</code> still packages for handling maps in R?</p>