Inspector : Prefer std::variant to boost::variant

include/GafferSceneUI/Private/Inspector.h

@@ -51,10 +51,10 @@
 #include "boost/multi_index/member.hpp"
 #include "boost/multi_index/random_access_index.hpp"
 #include "boost/multi_index_container.hpp"
-#include "boost/variant.hpp"
 
 #include <unordered_set>
 #include <unordered_map>
+#include <variant>
 
 namespace GafferSceneUIModule
 {
@@ -171,7 +171,7 @@ class GAFFERSCENEUI_API Inspector : public IECore::RefCounted, public Gaffer::Si
 		virtual Gaffer::ValuePlugPtr source( const GafferScene::SceneAlgo::History *history, std::string &editWarning ) const;
 
 		using EditFunction = std::function<Gaffer::ValuePlugPtr ( bool createIfNecessary )>;
-		using EditFunctionOrFailure = boost::variant<EditFunction, std::string>;
+		using EditFunctionOrFailure = std::variant<EditFunction, std::string>;
 		/// Should be implemented to return a function that will acquire
 		/// an edit from the EditScope at the specified point in the history.
 		/// If this is not possible, should return an error explaining why
@@ -184,7 +184,7 @@ class GAFFERSCENEUI_API Inspector : public IECore::RefCounted, public Gaffer::Si
 		virtual EditFunctionOrFailure editFunction( Gaffer::EditScope *editScope, const GafferScene::SceneAlgo::History *history ) const;
 
 		using DisableEditFunction = std::function<void ()>;
-		using DisableEditFunctionOrFailure = boost::variant<DisableEditFunction, std::string>;
+		using DisableEditFunctionOrFailure = std::variant<DisableEditFunction, std::string>;
 		/// Can be implemented to return a function that will disable an edit
 		/// at the specified plug. If this is not possible, should return an
 		/// error explaining why (this is typically due to `readOnly` metadata).

src/GafferSceneUI/Inspector.cpp

@@ -732,52 +732,54 @@ const std::string &Inspector::Result::fallbackDescription() const
 
 bool Inspector::Result::editable() const
 {
-	return m_editFunction.which() == 0 && boost::get<EditFunction>( m_editFunction ) != nullptr;
+	auto f = std::get_if<EditFunction>( &m_editFunction );
+	return f && *f;
 }
 
 std::string Inspector::Result::nonEditableReason() const
 {
-	if( m_editFunction.which() == 1 )
+	if( auto s = std::get_if<std::string>( &m_editFunction ) )
 	{
-		return boost::get<std::string>( m_editFunction );
+		return *s;
 	}
 
 	return "";
 }
 
 Gaffer::ValuePlugPtr Inspector::Result::acquireEdit( bool createIfNecessary ) const
 {
-	if( m_editFunction.which() == 0 )
+	if( auto f = std::get_if<EditFunction>( &m_editFunction ) )
 	{
-		return boost::get<EditFunction>( m_editFunction )( createIfNecessary );
+		return (*f)( createIfNecessary );
 	}
 
-	throw IECore::Exception( "Not editable : " + boost::get<std::string>( m_editFunction ) );
+	throw IECore::Exception( "Not editable : " + std::get<std::string>( m_editFunction ) );
 }
 
 bool Inspector::Result::canDisableEdit() const
 {
-	return m_disableEditFunction.which() == 0 && boost::get<DisableEditFunction>( m_disableEditFunction ) != nullptr;
+	auto f = std::get_if<DisableEditFunction>( &m_disableEditFunction );
+	return f && *f;
 }
 
 std::string Inspector::Result::nonDisableableReason() const
 {
-	if( m_disableEditFunction.which() == 1 )
+	if( auto s = std::get_if<std::string>( &m_disableEditFunction ) )
 	{
-		return boost::get<std::string>( m_disableEditFunction );
+		return *s;
 	}
 
 	return "";
 }
 
 void Inspector::Result::disableEdit() const
 {
-	if( m_disableEditFunction.which() == 0 )
+	if( auto f = std::get_if<DisableEditFunction>( &m_disableEditFunction ) )
 	{
-		return boost::get<DisableEditFunction>( m_disableEditFunction )();
+		return (*f)();
 	}
 
-	throw IECore::Exception( "Cannot disable edit : " + boost::get<std::string>( m_disableEditFunction ) );
+	throw IECore::Exception( "Cannot disable edit : " + std::get<std::string>( m_disableEditFunction ) );
 }
 
 std::string Inspector::Result::editWarning() const