diff --git a/include/json/value.h b/include/json/value.h
index 3fdd884..71bc65c 100644
--- a/include/json/value.h
+++ b/include/json/value.h
@@ -54,7 +54,7 @@ namespace Json {
  */
 class JSON_API Exception : public std::exception {
 public:
-  Exception(JSONCPP_STRING const& msg);
+  Exception(JSONCPP_STRING msg);
   ~Exception() JSONCPP_NOEXCEPT override;
   char const* what() const JSONCPP_NOEXCEPT override;
 
diff --git a/include/json/writer.h b/include/json/writer.h
index 7faaa02..34e71ed 100644
--- a/include/json/writer.h
+++ b/include/json/writer.h
@@ -300,8 +300,8 @@ public:
   /**
    * \param indentation Each level will be indented by this amount extra.
    */
-  StyledStreamWriter(const JSONCPP_STRING& indentation = "\t");
-  ~StyledStreamWriter() {}
+  StyledStreamWriter(JSONCPP_STRING indentation = "\t");
+  ~StyledStreamWriter() = default;
 
 public:
   /** \brief Serialize a Value in <a HREF="http://www.json.org">JSON</a> format.
diff --git a/src/lib_json/json_reader.cpp b/src/lib_json/json_reader.cpp
index ce4aac4..c5af014 100644
--- a/src/lib_json/json_reader.cpp
+++ b/src/lib_json/json_reader.cpp
@@ -88,9 +88,8 @@ bool Reader::containsNewLine(Reader::Location begin, Reader::Location end) {
 // //////////////////////////////////////////////////////////////////
 
 Reader::Reader()
-    : errors_(), document_(), begin_(), end_(), current_(), lastValueEnd_(),
-      lastValue_(), commentsBefore_(), features_(Features::all()),
-      collectComments_() {}
+    : errors_(), document_(), commentsBefore_(), features_(Features::all())
+      {}
 
 Reader::Reader(const Features& features)
     : errors_(), document_(), begin_(), end_(), current_(), lastValueEnd_(),
diff --git a/src/lib_json/json_value.cpp b/src/lib_json/json_value.cpp
index ef95117..2445d31 100644
--- a/src/lib_json/json_value.cpp
+++ b/src/lib_json/json_value.cpp
@@ -213,7 +213,7 @@ static inline void releaseStringValue(char* value, unsigned) { free(value); }
 
 namespace Json {
 
-Exception::Exception(JSONCPP_STRING const& msg) : msg_(msg) {}
+Exception::Exception(JSONCPP_STRING  msg) : msg_(std::move(msg)) {}
 Exception::~Exception() JSONCPP_NOEXCEPT {}
 char const* Exception::what() const JSONCPP_NOEXCEPT { return msg_.c_str(); }
 RuntimeError::RuntimeError(JSONCPP_STRING const& msg) : Exception(msg) {}
diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp
index 993001c..54fcb4f 100644
--- a/src/lib_json/json_writer.cpp
+++ b/src/lib_json/json_writer.cpp
@@ -642,8 +642,8 @@ bool StyledWriter::hasCommentForValue(const Value& value) {
 // Class StyledStreamWriter
 // //////////////////////////////////////////////////////////////////
 
-StyledStreamWriter::StyledStreamWriter(const JSONCPP_STRING& indentation)
-    : document_(nullptr), rightMargin_(74), indentation_(indentation),
+StyledStreamWriter::StyledStreamWriter(JSONCPP_STRING indentation)
+    : document_(nullptr), indentation_(std::move(indentation)),
       addChildValues_(), indented_(false) {}
 
 void StyledStreamWriter::write(JSONCPP_OSTREAM& out, const Value& root) {
@@ -872,11 +872,11 @@ struct CommentStyle {
 };
 
 struct BuiltStyledStreamWriter : public StreamWriter {
-  BuiltStyledStreamWriter(JSONCPP_STRING const& indentation,
+  BuiltStyledStreamWriter(JSONCPP_STRING indentation,
                           CommentStyle::Enum cs,
-                          JSONCPP_STRING const& colonSymbol,
-                          JSONCPP_STRING const& nullSymbol,
-                          JSONCPP_STRING const& endingLineFeedSymbol,
+                          JSONCPP_STRING colonSymbol,
+                          JSONCPP_STRING nullSymbol,
+                          JSONCPP_STRING endingLineFeedSymbol,
                           bool useSpecialFloats,
                           unsigned int precision,
                           PrecisionType precisionType);
@@ -912,17 +912,17 @@ private:
   PrecisionType precisionType_;
 };
 BuiltStyledStreamWriter::BuiltStyledStreamWriter(
-    JSONCPP_STRING const& indentation,
+    JSONCPP_STRING indentation,
     CommentStyle::Enum cs,
-    JSONCPP_STRING const& colonSymbol,
-    JSONCPP_STRING const& nullSymbol,
-    JSONCPP_STRING const& endingLineFeedSymbol,
+    JSONCPP_STRING colonSymbol,
+    JSONCPP_STRING nullSymbol,
+    JSONCPP_STRING endingLineFeedSymbol,
     bool useSpecialFloats,
     unsigned int precision,
     PrecisionType precisionType)
-    : rightMargin_(74), indentation_(indentation), cs_(cs),
-      colonSymbol_(colonSymbol), nullSymbol_(nullSymbol),
-      endingLineFeedSymbol_(endingLineFeedSymbol), addChildValues_(false),
+    : rightMargin_(74), indentation_(std::move(indentation)), cs_(cs),
+      colonSymbol_(std::move(colonSymbol)), nullSymbol_(std::move(nullSymbol)),
+      endingLineFeedSymbol_(std::move(endingLineFeedSymbol)), addChildValues_(false),
       indented_(false), useSpecialFloats_(useSpecialFloats),
       precision_(precision), precisionType_(precisionType) {}
 int BuiltStyledStreamWriter::write(Value const& root, JSONCPP_OSTREAM* sout) {