title: Plotting square function with ggplot2 geom_line?
body: <p>How can I use ggplot2's <code>geom_line</code> to plot a square function, where x,y coordinates are connected by squares rather than by lines? </p>
  
  <p>Something that looks like:</p>
  
  <p><img src="https://i.stack.imgur.com/9FeU4.gif" alt="enter image description here"></p>
  
  <p>Is this possible?</p>