added --version to arguments; refs #7

src/mrw/args.hxx

@@ -4,8 +4,8 @@
 */
 //       1         2         3         4         5         6         7         8
 // 45678901234567890123456789012345678901234567890123456789012345678901234567890
-#ifndef __MRW__
+#ifndef __MRW_ARGS__
-#define __MRW__
+#define __MRW_ARGS__
 
 #include <mrw/checkcxx11.hxx>
 #include <mrw/iomanip.hxx>
@@ -26,6 +26,10 @@
           @refs MRW__OLD_PRE11_COMPILER is set.
     */
 
+// Add version information for @c what and @c ident
+const std::string MRW_IDENT("$Id: " PACKAGENAME "-" PACKAGEVERSION " $");
+const std::string MRW_WHAT("#(@)" PACKAGENAME "-" PACKAGEVERSION);
+
 namespace mrw {
   /// Cool and easy evaluation of commandline arguments in C++11.
   /** Evaluating command line arguments is extremely easy with this library:
@@ -44,6 +48,7 @@ namespace mrw {
           args::parse(argc, argv, "This is an example for argument processing.",
                       {
             {"h", "help", "show this help", {args::help(), args::exit()}},
+            {"v", "version", "show version", {args::version(), args::exit()}},
             {"r", "repeat", "number of repetitions",
              {args::param(r, "number")}},
             {"f", "flag", "check a flag", {args::param(flag)}},
@@ -332,6 +337,26 @@ namespace mrw {
         std::cout<<std::endl;
       }
     }
+    /// @return version information
+    std::string version_text() {
+#     ifdef PACKAGEVERSION
+#       ifdef PACKAGENAME
+          std::string v(": " PACKAGENAME "-" PACKAGEVERSION);
+#       else
+          std::string v("-" PACKAGEVERSION);
+#       endif
+#     else
+#       ifdef PACKAGENAME
+          std::string v(": " PACKAGENAME);
+#       else
+          std::string v;
+#       endif
+#     endif
+      return filename() + v;
+    }
+    void show_version() {
+      std::cout<<version_text()<<std::endl;
+    }
     void help_no_arg() {
       show_help();
     }
@@ -344,9 +369,32 @@ namespace mrw {
     param_ptr help() {
       return func(args::help_no_arg);
     }
+    param_ptr version() {
+      return func(args::show_version);
+    }
     param_ptr exit() {
       return func(args::do_exit);
     }
+    /// Sets up an argument list containing help and version.
+    list defaults() {
+#ifdef MRW__OLD_PRE11_COMPILER
+      list res;
+      decl::param_list h;
+      h.push_back(help());
+      h.push_back(exit());
+      decl::param_list v;
+      v.push_back(version());
+      v.push_back(exit());
+      res.push_back(decl("h", "help", "show help", h));
+      res.push_back(decl("v", "version", "show version", v));
+      return res;
+#else // New C++ standard C++11 is great:
+      return list({
+          {"h", "help", "show help", {help(), exit()}},
+          {"v", "version", "show version", {version(), exit()}}
+        });
+#endif
+    }
   }
 }
 #endif