[clang-tidy] Use default to initialize constructors

Found with modernize-use-equals-default

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/CLI2.cpp

@@ -49,21 +49,10 @@ A2::A2 (const std::string& raw, Lexer::Type lextype)
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-A2::A2 (const A2& other)
+A2::A2 (const A2& other) = default;
-: _lextype (other._lextype)
-, _tags (other._tags)
-, _attributes (other._attributes)
-{
-}
 
 ////////////////////////////////////////////////////////////////////////////////
-A2& A2::operator= (const A2& other)
+A2& A2::operator= (const A2& other) = default;
-{
-  _lextype    = other._lextype;
-  _tags       = other._tags;
-  _attributes = other._attributes;
-  return *this;
-}
 
 ////////////////////////////////////////////////////////////////////////////////
 bool A2::hasTag (const std::string& tag) const

src/Lexer.cpp

@@ -50,9 +50,7 @@ Lexer::Lexer (const std::string& text)
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-Lexer::~Lexer ()
+Lexer::~Lexer () = default;
-{
-}
 
 ////////////////////////////////////////////////////////////////////////////////
 // When a Lexer object is constructed with a string, this method walks through

src/Variant.cpp

@@ -166,19 +166,7 @@ const std::string& Variant::source () const
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-Variant& Variant::operator= (const Variant& other)
+Variant& Variant::operator= (const Variant& other) = default;
-{
-  _type     = other._type;
-  _bool     = other._bool;
-  _integer  = other._integer;
-  _real     = other._real;
-  _string   = other._string;
-  _date     = other._date;
-  _duration = other._duration;
-  _source   = other._source;
-
-  return *this;
-}
 
 ////////////////////////////////////////////////////////////////////////////////
 bool Variant::operator&& (const Variant& other) const