fixed output of help text for program options

actor-framework · Nov 5, 2012 · 3c15db6 · 3c15db6
1 parent 5548468
commit 3c15db6
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Showing 2 changed files with 27 additions and 6 deletions.
diff --git a/cppa/opt.hpp b/cppa/opt.hpp
@@ -59,7 +59,12 @@ detail::add_arg_functor<T> add_arg(std::vector<T>& storage) {
     return {storage};
 }
 
-typedef std::map<std::string, std::map<std::pair<char, std::string>, std::string> >
+struct option_info {
+    std::string help_text;
+    size_t num_args;
+};
+
+typedef std::map<std::string,std::map<std::pair<char,std::string>,option_info> >
         options_description;
 
 detail::opt_rvalue_builder<true> on_opt(char short_opt,

diff --git a/src/opt.cpp b/src/opt.cpp
@@ -43,7 +43,8 @@ detail::opt_rvalue_builder<true> on_opt(char short_opt,
                                         string help_text,
                                         string help_group) {
     if (desc) {
-        (*desc)[help_group].insert(make_pair(make_pair(short_opt, long_opt), help_text));
+        option_info oinf{help_text, 1};
+        (*desc)[help_group].insert(make_pair(make_pair(short_opt, long_opt), move(oinf)));
     }
     const char short_flag_arr[] = {'-', short_opt, '\0' };
     const char* lhs_str = short_flag_arr;
@@ -73,7 +74,8 @@ on_vopt(char short_opt,
         string help_text,
         string help_group) {
     if (desc) {
-        (*desc)[help_group].insert(make_pair(make_pair(short_opt, long_opt), help_text));
+        option_info oinf{help_text, 0};
+        (*desc)[help_group].insert(make_pair(make_pair(short_opt, long_opt), move(oinf)));
     }
     const char short_flag_arr[] = {'-', short_opt, '\0' };
     vector<string> opt_strs = { short_flag_arr };
@@ -85,6 +87,10 @@ on_vopt(char short_opt,
 function<void()> print_desc(options_description* desc, ostream& out) {
     return [&out, desc] {
         if (!desc) return;
+        if (desc->empty()) {
+            out << "please use '-h' or '--help' for a list "
+                   "of available program options\n";
+        }
         for (auto& opt_group : *desc) {
             out << opt_group.first << ":\n";
             for (auto& opt : opt_group.second) {
@@ -93,10 +99,20 @@ function<void()> print_desc(options_description* desc, ostream& out) {
                 ostringstream tmp;
                 auto& names = opt.first;
                 if (names.first != '\0') {
-                    tmp << "-" << names.first << " <arg> | ";
+                    tmp << "-" << names.first;
+                    for (size_t num = 1; num <= opt.second.num_args; ++num) {
+                        tmp << " <arg" << num << ">";
+                    }
+                    tmp << " | ";
+                }
+                tmp << "--" << names.second;
+                if (opt.second.num_args > 0) {
+                    tmp << "=<arg1>";
+                }
+                for (size_t num = 2; num <= opt.second.num_args; ++num) {
+                    tmp << ",<arg" << num << ">";
                 }
-                tmp << "--" << names.second << " <arg>";
-                out << tmp.str() << opt.second << "\n";
+                out << tmp.str() << opt.second.help_text << "\n";
             }
             out << "\n";
         }