Start a set of simple examples.

* examples/calc++/Makefile, examples/calc++/calc++-driver.cc,
* examples/calc++/calc++-driver.hh,
* examples/calc++/calc++-parser.yy,
* examples/calc++/calc++-scanner.ll, examples/calc++/calc++.cc,
* examples/calc++/compile, examples/calc++/test: New.

examples/calc++/calc++.cc

@@ -0,0 +1,18 @@
+#include <iostream>
+#include "calc++-driver.hh"
+
+int
+main (int argc, const char* argv[])
+{
+  calcxx_driver driver;
+  for (++argv; argv[0]; ++argv)
+    if (*argv == std::string ("-p"))
+      driver.trace_parsing = true;
+    else if (*argv == std::string ("-s"))
+      driver.trace_scanning = true;
+    else
+      {
+	driver.parse (*argv);
+	std::cout << driver.result << std::endl;
+      }
+}