From 5fc954e4a39c050995569541461800339bc92bfb Mon Sep 17 00:00:00 2001
From: Hans Johnson <hans-johnson@uiowa.edu>
Date: Fri, 27 Dec 2024 13:50:14 -0600
Subject: [PATCH] PERF: Prefer default initialization for std::string

Return {} may be the fastest, because it just calls the
default-constructor of std::string.  (return { "" } and return "" may be
slightly slower because they convert a literal string to an std::string.

This probably does not have a substantive impact on the current
uses, but implementing to keep the style consistent.
---
 Modules/Core/Common/src/itkBuildInformation.cxx.in            | 4 ++--
 .../SpatialObjects/include/itkDTITubeSpatialObjectPoint.hxx   | 2 +-
 .../src/itkPolygonGroupSpatialObjectXMLFile.cxx               | 2 +-
 Modules/Numerics/Optimizers/src/itkLBFGSOptimizer.cxx         | 2 +-
 Modules/Numerics/Optimizersv4/src/itkLBFGSOptimizerv4Base.cxx | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/Modules/Core/Common/src/itkBuildInformation.cxx.in b/Modules/Core/Common/src/itkBuildInformation.cxx.in
index ad4cf9026df..6e70541cd56 100644
--- a/Modules/Core/Common/src/itkBuildInformation.cxx.in
+++ b/Modules/Core/Common/src/itkBuildInformation.cxx.in
@@ -87,7 +87,7 @@ BuildInformation::GetValue(const MapKeyType & key)
   {
     return it->second.m_Value;
   }
-  return {""};
+  return {};;
 }
 
 const BuildInformation::MapValueDescriptionType
@@ -100,7 +100,7 @@ BuildInformation::GetDescription(const MapKeyType & key)
   {
     return it->second.m_Description;
   }
-  return {""};
+  return {};;
 }
 
 const std::vector<  BuildInformation::MapKeyType >
diff --git a/Modules/Core/SpatialObjects/include/itkDTITubeSpatialObjectPoint.hxx b/Modules/Core/SpatialObjects/include/itkDTITubeSpatialObjectPoint.hxx
index 60275eca396..22a5e2ce9f3 100644
--- a/Modules/Core/SpatialObjects/include/itkDTITubeSpatialObjectPoint.hxx
+++ b/Modules/Core/SpatialObjects/include/itkDTITubeSpatialObjectPoint.hxx
@@ -64,7 +64,7 @@ DTITubeSpatialObjectPoint<TPointDimension>::TranslateEnumToChar(DTITubeSpatialOb
       // Just fall through.
       break;
   }
-  return { "" };
+  return {};
 }
 
 template <unsigned int TPointDimension>
diff --git a/Modules/IO/SpatialObjects/src/itkPolygonGroupSpatialObjectXMLFile.cxx b/Modules/IO/SpatialObjects/src/itkPolygonGroupSpatialObjectXMLFile.cxx
index 766526e7330..4a4e5b557df 100644
--- a/Modules/IO/SpatialObjects/src/itkPolygonGroupSpatialObjectXMLFile.cxx
+++ b/Modules/IO/SpatialObjects/src/itkPolygonGroupSpatialObjectXMLFile.cxx
@@ -165,7 +165,7 @@ class NumericTraits<std::string>
   static std::string
   ZeroValue()
   {
-    return { "" };
+    return {};
   }
 };
 
diff --git a/Modules/Numerics/Optimizers/src/itkLBFGSOptimizer.cxx b/Modules/Numerics/Optimizers/src/itkLBFGSOptimizer.cxx
index deced1e046c..ea8366221b3 100644
--- a/Modules/Numerics/Optimizers/src/itkLBFGSOptimizer.cxx
+++ b/Modules/Numerics/Optimizers/src/itkLBFGSOptimizer.cxx
@@ -315,6 +315,6 @@ LBFGSOptimizer::GetStopConditionDescription() const
     return m_StopConditionDescription.str();
   }
 
-  return { "" };
+  return {};
 }
 } // end namespace itk
diff --git a/Modules/Numerics/Optimizersv4/src/itkLBFGSOptimizerv4Base.cxx b/Modules/Numerics/Optimizersv4/src/itkLBFGSOptimizerv4Base.cxx
index 5d8eb92ac89..e4130368bac 100644
--- a/Modules/Numerics/Optimizersv4/src/itkLBFGSOptimizerv4Base.cxx
+++ b/Modules/Numerics/Optimizersv4/src/itkLBFGSOptimizerv4Base.cxx
@@ -213,7 +213,7 @@ LBFGSOptimizerBasev4<TInternalVnlOptimizerType>::GetStopConditionDescription() c
     return m_StopConditionDescription.str();
   }
 
-  return { "" };
+  return {};
 }
 
 template class ITKOptimizersv4_EXPORT LBFGSOptimizerBasev4<vnl_lbfgs>;