title: How to learn R as a programming language
body: <p>I'd like to know how to learn the R language as as 'programming' language as opposed to learning it as a statistical system. My question is prompted by lack of understanding of such functions as parse, eval, etc. which may not find frequent use by an R user with a 'statistics' persuasion.</p>
  
  <p>Edit: I've been exploring such tools like Rpy RSPerl rJava and wish to (at the very least) be able to understand concepts that facilitate R's communication with other programming languages. </p>
  
  <p>The availability of Web applications for R (R-PHP, RApache, etc.) is another motivationg factor for me to gain a deeper, more structural understanding of R.</p>
  
  <p>Last but not the least, I'd like to be able to write R packages for which such understanding would be beneficial if not necessary.</p>