added second part of evaluation in cpp

gnuplot-iostream/legacy/examples-framework.cc

@@ -0,0 +1,55 @@
+/*
+Copyright (c) 2013 Daniel Stahlke
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include <map>
+#include <cstdio>
+#include <boost/foreach.hpp>
+
+std::map<std::string, void (*)(void)> demos;
+
+void register_demo(const std::string &label, void (*fn)(void)) {
+	demos[label] = fn;
+}
+
+void register_demos();
+
+int main(int argc, char **argv) {
+	register_demos();
+
+	if(argc < 2) {
+		printf("Usage: %s <demo_name>\n", argv[0]);
+		printf("Choose one of the following demos:\n");
+		typedef std::pair<std::string, void (*)(void)> demo_pair;
+		BOOST_FOREACH(const demo_pair &pair, demos) {
+			printf("    %s\n", pair.first.c_str());
+		}
+		return 0;
+	}
+
+	std::string arg(argv[1]);
+	if(!demos.count(arg)) {
+		printf("No such demo '%s'\n", arg.c_str());
+		return 1;
+	}
+
+	demos[arg]();
+}