failed conversion of enums results in error dialog, in debug mode

The make_enum macro header now includes wml_exception.hpp, and
game_config. We use the FAIL macro to launch a transient
twml_exception dialog when an enum is casted from an illegal
string value. This means that when enums in our C++ classes are
initialized using lexical_cast<enum_type> (cfg["attribute"]),
we will automatically give error reports for bad values.

src/make_enum.hpp

@@ -68,13 +68,25 @@ MAKE_ENUM_STREAM_OPS2(bar , another)
  * foo::enumname_to_string(foo::enumname);                      //no throw
  * 
  * The stream ops define
- * std::ostream & operator<< (std::ostream &, foo::enumname)
- * std::istream & operator>> (std::istream &, foo::enumname &)
+ * std::ostream & operator<< (std::ostream &, foo::enumname)    //no throw. asserts false if enum has an illegal value.
+ * std::istream & operator>> (std::istream &, foo::enumname &)  //throws twml_exception including line number and arguments, IF game_config::debug is true.
+ * 								//doesn't throw except in that case, and correctly sets istream state to failing always.
+ *								//this is generally a recoverable exception that only shows a temporary dialog box,
+ *								//and is caught at many places in the gui code. you may safely catch it and ignore it,
+ *								//and then proceeding, or use a wrapper like lexical_cast_default which will assign the
+ *								//default value and proceed after the dialog passes.
  *
  * In case of a bad string -> enum conversion from istream output, 
  * the istream will have its fail bit set.
  * This means that lexical_casts will throw a bad_lexical_cast,
- * in the similar scenario.
+ * in the similar scenario. (but, that exception won't have any
+ * details about the error.)
+ *
+ * It is recommended to use this type either the built-in wesnoth
+ * lexical_cast or lexical_cast default. 
+ *
+ * HOWEVER, if you DON'T want twml_exceptions to be thrown in any
+ * circumstance, then use the string_to_enumname functions instead.
  *
  * To get lexical_cast, you must separately include util.hpp
  *
@@ -87,7 +99,9 @@ MAKE_ENUM_STREAM_OPS2(bar , another)
 #ifndef MAKE_ENUM_HPP
 #define MAKE_ENUM_HPP
 
+#include "game_config.hpp"
 #include "global.hpp"
+#include "wml_exception.hpp"
 
 #include <boost/preprocessor/cat.hpp>
 #include <boost/preprocessor/seq/for_each.hpp>
@@ -189,6 +203,9 @@ inline std::istream& operator>> (std::istream & is, NAME & val) \
 		val = CAT2(string_to_, NAME) ( temp ); \
 	} catch (bad_enum_cast & e) { \
 		is.setstate(std::ios::failbit); \
+		if (game_config::debug) { \
+			FAIL( e.what() ); \
+		} \
 	} \
 	return is; \
 } \
@@ -210,6 +227,9 @@ inline std::istream& operator>> (std::istream & is, NAMESPACE::NAME & val) \
 		val = CAT2(NAMESPACE::string_to_,NAME) ( temp ); \
 	} catch (bad_enum_cast & e) {\
 		is.setstate(std::ios::failbit); \
+		if (game_config::debug) { \
+			FAIL( e.what() ); \
+		} \
 	} \
 	return is; \
 } \

src/team.cpp

@@ -131,7 +131,7 @@ void team::team_info::read(const config &cfg)
 	allow_player = cfg["allow_player"].to_bool(true);
 	chose_random = cfg["chose_random"].to_bool(false);
 	no_leader = cfg["no_leader"].to_bool();
-	defeat_condition = team::string_to_DEFEAT_CONDITION_default(cfg["defeat_condition"], team::NO_LEADER);
+	defeat_condition = lexical_cast_default<team::DEFEAT_CONDITION>(cfg["defeat_condition"], team::NO_LEADER);
 	hidden = cfg["hidden"].to_bool();
 	no_turn_confirmation = cfg["suppress_end_turn_confirmation"].to_bool();
 	side = cfg["side"].to_int(1);
@@ -258,7 +258,7 @@ void team::team_info::write(config& cfg) const
 	cfg["allow_player"] = allow_player;
 	cfg["chose_random"] = chose_random;
 	cfg["no_leader"] = no_leader;
-	cfg["defeat_condition"] = team::DEFEAT_CONDITION_to_string(defeat_condition);
+	cfg["defeat_condition"] = lexical_cast<std::string>(defeat_condition);
 	cfg["hidden"] = hidden;
 	cfg["suppress_end_turn_confirmation"] = no_turn_confirmation;
 	cfg["scroll_to_leader"] = scroll_to_leader;

src/team.hpp

@@ -277,7 +277,7 @@ class team : public savegame::savegame_config
 	DEFEAT_CONDITION defeat_condition() const { return info_.defeat_condition; }
 	void set_defeat_condition(DEFEAT_CONDITION value) { info_.defeat_condition = value; }
 	///sets the defeat condition if @param value is a valid defeat condition, otherwise nothing happes.
-	void set_defeat_condition_string(const std::string& value) { info_.defeat_condition = string_to_DEFEAT_CONDITION_default(value, info_.defeat_condition); }
+	void set_defeat_condition_string(const std::string& value) { info_.defeat_condition = lexical_cast_default<team::DEFEAT_CONDITION>(value, info_.defeat_condition); }
 	void have_leader(bool value=true) { info_.no_leader = !value; }
 	bool hidden() const { return info_.hidden; }
 	void set_hidden(bool value) { info_.hidden=value; }