Rearrange GetOpt internals to provide a nicer external interface

[libs/core.git] / source / core / getopt.h

diff --git a/source/core/getopt.h b/source/core/getopt.h
index 8e0f49a3fb9d12c83d986289e6cf69d5fc10cee9..d3369c6b46fdf57b392b5a8dc56507fc6b79a773 100644 (file)
--- a/source/core/getopt.h
+++ b/source/core/getopt.h
@@ -1,20 +1,27 @@
-/* $Id$
-
-This file is part of libmspcore
-Copyright © 2006-2009, 2011 Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
-
 #ifndef MSP_CORE_GETOPT_H_
 #define MSP_CORE_GETOPT_H_
 
-#include <sstream>
+#include <list>
+#include <stdexcept>
 #include <string>
 #include <vector>
-#include "except.h"
+#include <msp/strings/lexicalcast.h>
 
 namespace Msp {
 
+class usage_error: public std::runtime_error
+{
+private:
+       std::string help_;
+
+public:
+       usage_error(const std::string &w, const std::string &h = std::string()): std::runtime_error(w), help_(h) { }
+       ~usage_error() throw() { }
+
+       const char *help() const throw() { return help_.c_str(); }
+};
+
+
 class GetOpt
 {
 public:
@@ -25,7 +32,20 @@ public:
                REQUIRED_ARG
        };
        
-       class OptBase
+       class Option
+       {
+       protected:
+               Option() { }
+       public:
+               virtual ~Option() { }
+
+               virtual Option &set_help(const std::string &) = 0;
+               virtual Option &set_help(const std::string &, const std::string &) = 0;
+               virtual unsigned get_seen_count() const = 0;
+       };
+
+private:
+       class OptBase: public Option
        {
        protected:
                char shrt;
@@ -39,14 +59,14 @@ public:
        public:
                virtual ~OptBase() { }
 
-               OptBase &set_help(const std::string &);
-               OptBase &set_help(const std::string &, const std::string &);
+               virtual OptBase &set_help(const std::string &);
+               virtual OptBase &set_help(const std::string &, const std::string &);
                char get_short() const { return shrt; }
                const std::string &get_long() const { return lng; }
                ArgType get_arg_type() const { return arg_type; }
                const std::string &get_help() const { return help; }
                const std::string &get_metavar() const { return metavar; }
-               unsigned get_seen_count() const { return seen_count; }
+               virtual unsigned get_seen_count() const { return seen_count; }
                void process();
                void process(const std::string &);
        protected:
@@ -54,73 +74,80 @@ public:
                virtual void store(const std::string &) = 0;
        };
 
-private:
        template<typename T>
-       class Option: public OptBase
+       class SimpleOption: public OptBase
        {
+       private:
+               T &data;
+
        public:
-               Option(char s, const std::string &l, T &d, ArgType a): OptBase(s, l, a), data(d) { }
+               SimpleOption(char s, const std::string &l, T &d, ArgType a): OptBase(s, l, a), data(d) { }
 
                virtual void store() { }
 
                virtual void store(const std::string &a)
                {
-                       T tmp;
-                       std::istringstream ss(a);
-                       ss>>tmp;
-                       if(ss.fail())
-                               throw UsageError("Invalid argument for --"+lng);
-
-                       data = tmp;
+                       try
+                       {
+                               data = lexical_cast<T>(a);
+                       }
+                       catch(const lexical_error &e)
+                       {
+                               throw usage_error("Invalid argument for --"+lng+" ("+e.what()+")");
+                       }
                }
-       private:
-               T &data;
        };
 
        template<typename T>
        class ListOption: public OptBase
        {
+       private:
+               T &data;
+
        public:
                ListOption(char s, const std::string &l, T &d, ArgType a): OptBase(s, l, a), data(d)
-               { if(arg_type!=REQUIRED_ARG) throw Exception("ListOption with arg_type!=REQUIRED makes no sense"); }
+               { if(arg_type!=REQUIRED_ARG) throw std::invalid_argument("ListOption arg_type!=REQUIRED"); }
 
                virtual void store() { }
 
                virtual void store(const std::string &a)
                {
-                       typename T::value_type tmp;
-                       std::istringstream ss(a);
-                       ss>>tmp;
-                       if(ss.fail())
-                               throw UsageError("Invalid argument for --"+lng);
-
-                       data.push_back(tmp);
+                       try
+                       {
+                               data.push_back(lexical_cast<typename T::value_type>(a));
+                       }
+                       catch(const lexical_error &e)
+                       {
+                               throw usage_error("Invalid argument for --"+lng+" ("+e.what()+")");
+                       }
                }
-       private:
-               T &data;
        };
 
+       bool help;
        std::list<OptBase *> opts;
        std::vector<std::string> args;
 
 public:
+       GetOpt();
        ~GetOpt();
 
        const std::vector<std::string> &get_args() const { return args; }
 
        template<typename T>
-       OptBase &add_option(char s, const std::string &l, T &d, ArgType a = NO_ARG)
-       { opts.push_back(new Option<T>(s, l, d, a)); return *opts.back(); }
+       Option &add_option(char s, const std::string &l, T &d, ArgType a = NO_ARG)
+       { return add_option(new SimpleOption<T>(s, l, d, a)); }
        
        template<typename T>
-       OptBase &add_option(char s, const std::string &l, std::list<T> &d, ArgType a = REQUIRED_ARG)
-       { opts.push_back(new ListOption<std::list<T> >(s, l, d, a)); return *opts.back(); }
+       Option &add_option(char s, const std::string &l, std::list<T> &d, ArgType a = REQUIRED_ARG)
+       { return add_option(new ListOption<std::list<T> >(s, l, d, a)); }
        
        template<typename T>
-       OptBase &add_option(const std::string &l, T &d, ArgType a)
+       Option &add_option(const std::string &l, T &d, ArgType a)
        { return add_option(0, l, d, a); }
 
 private:
+       OptBase &add_option(OptBase *);
+
        OptBase &get_option(char);
        OptBase &get_option(const std::string &);
 
@@ -145,10 +172,13 @@ public:
        std::string generate_help() const;
 };
 
-template<> inline void GetOpt::Option<bool>::store()     { data = true; }
-template<> inline void GetOpt::Option<unsigned>::store() { ++data; }
+template<> inline void GetOpt::SimpleOption<bool>::store()
+{ data = true; }
+
+template<> inline void GetOpt::SimpleOption<unsigned>::store()
+{ ++data; }
 
-template<> inline void GetOpt::Option<std::string>::store(const std::string &a)
+template<> inline void GetOpt::SimpleOption<std::string>::store(const std::string &a)
 { data = a; }
 
 template<> inline void GetOpt::ListOption<std::list<std::string> >::store(const std::string &a)