STYLE: Use default member initialization

Converts a default constructor’s member initializers into the new
default member initializers in C++11. Other member initializers that match the
default member initializer are removed. This can reduce repeated code or allow
use of ‘= default’.

SRCDIR=/Users/johnsonhj/src/jsoncpp/ #My local SRC
BLDDIR=/Users/johnsonhj/src/jsoncpp/cmake-build-debug/ #My local BLD

cd /Users/johnsonhj/src/jsoncpp/cmake-build-debug/
run-clang-tidy.py -extra-arg=-D__clang__ -checks=-*,modernize-use-default-member-init  -header-filter=.* -fix

src/lib_json/json_reader.cpp

@@ -60,8 +60,7 @@ typedef std::auto_ptr<CharReader> CharReaderPtr;
 // ////////////////////////////////
 
 Features::Features()
-    : allowComments_(true), strictRoot_(false),
-      allowDroppedNullPlaceholders_(false), allowNumericKeys_(false) {}
+     {}
 
 Features Features::all() { return {}; }
 

src/lib_json/json_value.cpp

@@ -233,7 +233,7 @@ JSONCPP_NORETURN void throwLogicError(JSONCPP_STRING const& msg) {
 // //////////////////////////////////////////////////////////////////
 // //////////////////////////////////////////////////////////////////
 
-Value::CommentInfo::CommentInfo() : comment_(nullptr) {}
+Value::CommentInfo::CommentInfo()  {}
 
 Value::CommentInfo::~CommentInfo() {
   if (comment_)
@@ -1575,7 +1575,7 @@ Value::iterator Value::end() {
 // class PathArgument
 // //////////////////////////////////////////////////////////////////
 
-PathArgument::PathArgument() : key_(), index_(), kind_(kindNone) {}
+PathArgument::PathArgument() : key_() {}
 
 PathArgument::PathArgument(ArrayIndex index)
     : key_(), index_(index), kind_(kindIndex) {}

src/lib_json/json_valueiterator.inl

@@ -16,7 +16,7 @@ namespace Json {
 // //////////////////////////////////////////////////////////////////
 
 ValueIteratorBase::ValueIteratorBase()
-    : current_(), isNull_(true) {
+    : current_() {
 }
 
 ValueIteratorBase::ValueIteratorBase(

src/lib_json/json_writer.cpp

@@ -352,8 +352,8 @@ Writer::~Writer() {}
 // //////////////////////////////////////////////////////////////////
 
 FastWriter::FastWriter()
-    : yamlCompatibilityEnabled_(false), dropNullPlaceholders_(false),
-      omitEndingLineFeed_(false) {}
+    
+      {}
 
 void FastWriter::enableYAMLCompatibility() { yamlCompatibilityEnabled_ = true; }
 
@@ -428,7 +428,7 @@ void FastWriter::writeValue(const Value& value) {
 // //////////////////////////////////////////////////////////////////
 
 StyledWriter::StyledWriter()
-    : rightMargin_(74), indentSize_(3), addChildValues_(false) {}
+     {}
 
 JSONCPP_STRING StyledWriter::write(const Value& root) {
   document_.clear();