[clang-tidy] cpp: Turn reference operators to const

Found with cppcoreguidelines-c-copy-assignment-signature

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

1 files changed, 1 insertions, 1 deletions

diff --git a/include/plist/Real.h b/include/plist/Real.h
index c2d55f8..5afb0c0 100644
--- a/include/plist/Real.h
+++ b/include/plist/Real.h
@@ -33,7 +33,7 @@ public :
     Real(Node* parent = NULL);
     Real(plist_t node, Node* parent = NULL);
     Real(const Real& d);
-    Real& operator=(Real& d);
+    Real& operator=(const Real& d);
     Real(double d);
     virtual ~Real();