oc hacks using primitive tools such as
      <tt>scanf</tt>. True, there are tools such as regular-expression
      libraries (such as <a href=
      "http://www.boost.org/libs/regex/index.html">boost regex</a>) or scanners
      (such as <a href="http://www.boost.org/libs/tokenizer/index.html">boost
      tokenizer</a>), but these tools do not scale well when we need to write
      more elaborate parsers. Attempting to write even a moderately-complex
      parser using these tools leads to code that is har