From fdce4f38f0fe6f95d614484f15fb2a31d21f5626 Mon Sep 17 00:00:00 2001
From: Mike Smoot <mes@aescon.com>
Date: Sun, 22 May 2011 12:05:21 -0700
Subject: [PATCH] Allows xor args to be optional

---
 include/tclap/CmdLine.h          | 21 ++++++++++++---------
 include/tclap/CmdLineInterface.h |  6 ++++--
 2 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/include/tclap/CmdLine.h b/include/tclap/CmdLine.h
index 0fec8d8..fc47ed8 100644
--- a/include/tclap/CmdLine.h
+++ b/include/tclap/CmdLine.h
@@ -224,15 +224,17 @@ private:
 		 * not need to be called.
 		 * \param a - Argument to be added and xor'd.
 		 * \param b - Argument to be added and xor'd.
+		 * \param required - Require at least one option (defaults to true)
 		 */
-		void xorAdd( Arg& a, Arg& b );
+		void xorAdd( Arg& a, Arg& b, bool required=true );
 
 		/**
 		 * Add a list of Args that will be xor'd.  If this method is used,
 		 * add does not need to be called.
 		 * \param xors - List of Args to be added and xor'd.
+		 * \param required - Require at least one option (defaults to true)
 		 */
-		void xorAdd( std::vector<Arg*>& xors );
+		void xorAdd( std::vector<Arg*>& xors, bool required=true );
 
 		/**
 		 * Parses the command line.
@@ -390,24 +392,25 @@ inline void CmdLine::_constructor()
 	deleteOnExit(v);
 }
 
-inline void CmdLine::xorAdd( std::vector<Arg*>& ors )
+inline void CmdLine::xorAdd( std::vector<Arg*>& ors, bool required )
 {
 	_xorHandler.add( ors );
 
-	for (ArgVectorIterator it = ors.begin(); it != ors.end(); it++)
-	{
-		(*it)->forceRequired();
-		(*it)->setRequireLabel( "OR required" );
+	for (ArgVectorIterator it = ors.begin(); it != ors.end(); it++) {
+		if (required) {
+			(*it)->forceRequired();
+			(*it)->setRequireLabel( "OR required" );
+		}
 		add( *it );
 	}
 }
 
-inline void CmdLine::xorAdd( Arg& a, Arg& b )
+inline void CmdLine::xorAdd( Arg& a, Arg& b, bool required )
 {
 	std::vector<Arg*> ors;
 	ors.push_back( &a );
 	ors.push_back( &b );
-	xorAdd( ors );
+	xorAdd( ors, required );
 }
 
 inline void CmdLine::add( Arg& a )
diff --git a/include/tclap/CmdLineInterface.h b/include/tclap/CmdLineInterface.h
index 1b25e9b..9f17d70 100644
--- a/include/tclap/CmdLineInterface.h
+++ b/include/tclap/CmdLineInterface.h
@@ -67,15 +67,17 @@ class CmdLineInterface
 		 * not need to be called.
 		 * \param a - Argument to be added and xor'd. 
 		 * \param b - Argument to be added and xor'd. 
+		 * \param required - Require at least one option (defaults to true)
 		 */
-		virtual void xorAdd( Arg& a, Arg& b )=0;
+		virtual void xorAdd( Arg& a, Arg& b, bool required=true )=0;
 
 		/**
 		 * Add a list of Args that will be xor'd.  If this method is used, 
 		 * add does not need to be called.
 		 * \param xors - List of Args to be added and xor'd. 
+		 * \param required - Require at least one option (defaults to true)
 		 */
-		virtual void xorAdd( std::vector<Arg*>& xors )=0;
+		virtual void xorAdd( std::vector<Arg*>& xors, bool required=true )=0;
 
 		/**
 		 * Parses the command line.