diff --git a/libwccl/values/bool.h b/libwccl/values/bool.h
index 23cb432afb1d9dda647c4ab33e81c74bb459d1ee..e0e05c3bf3f556c669b4d62e8813e83022c29d74 100644
--- a/libwccl/values/bool.h
+++ b/libwccl/values/bool.h
@@ -23,7 +23,7 @@ public:
 		val_ = v;
 	}
 
-	bool equals(const Bool& other) {
+	bool equals(const Bool& other) const {
 		return val_ == other.val_;
 	}
 
diff --git a/libwccl/values/positionref.h b/libwccl/values/positionref.h
index d710278ff4245f68ab8555eaa57e73eb9ba74644..30de6cc8073675410877f09163211350282b0218 100644
--- a/libwccl/values/positionref.h
+++ b/libwccl/values/positionref.h
@@ -54,7 +54,7 @@ public:
 				(base_->get_value() == Position::End && offset_ > 0);
 	}
 
-	bool equals(const PositionRef& other) {
+	bool equals(const PositionRef& other) const {
 		return points_nowhere() ? other.points_nowhere()
 			: offset_ == other.offset_ && base_->equals(*other.base_);
 	}