title: Run code spread over multiple lines in single keystroke [r]
body: <p>Coding/R noob here.</p>
  
  <p>Say that I want to plot a histogram of my data. To keep it tidy (for me, at least) I've split the parameters over multiple lines:</p>
  
  <pre><code>hist(data,
      density=20,     
      ylim=c(0,1),
      xlim=c(0,1),  
      freq=FALSE,
      xlab="X axis",
      ylab="Y axis",
      breaks=25)
  
  curve(dnorm(x,mean, sd),
      col="black",
      add=TRUE,
      lwd=1.5)
  </code></pre>
  
  <p>Now I want to change just one or two of the parameters, and then re-run this whole sequence. If I had everything on one line I could run it all with one keystroke. Now R wants no less than 8 keystrokes to re-run this specific section of code. I could of course select the whole block and run it, but that seems a bit fiddly. I could also use "run previous", but that also gets a bit messy when superimposing graphs, since R doesn't have an "undo plot", so you need to re-run everything if your line width is too broad the first time around.</p>
  
  <p>Is there another way, a la { } or something?</p>