X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?a=blobdiff_plain;f=lib%2Fmstch%2Fvisitor%2Fis_node_empty.hpp;fp=lib%2Fmstch%2Fvisitor%2Fis_node_empty.hpp;h=a0ae432e0c4d7cafd0057ffb2b2c8f33616d026a;hb=2e142df11d6f312a2a2b5097b8da73571ed523e8;hp=0000000000000000000000000000000000000000;hpb=61b3659afe961ed248f30e26f9ca8f28fcfafddc;p=cpPlugins.git

diff --git a/lib/mstch/visitor/is_node_empty.hpp b/lib/mstch/visitor/is_node_empty.hpp
new file mode 100644
index 0000000..a0ae432
--- /dev/null
+++ b/lib/mstch/visitor/is_node_empty.hpp
@@ -0,0 +1,41 @@
+#pragma once
+
+#include <boost/variant/static_visitor.hpp>
+
+#include "mstch/mstch.hpp"
+
+namespace mstch {
+
+class is_node_empty: public boost::static_visitor<bool> {
+ public:
+  template<class T>
+  bool operator()(const T&) const {
+    return false;
+  }
+
+  bool operator()(const std::nullptr_t&) const {
+    return true;
+  }
+
+  bool operator()(const int& value) const {
+    return value == 0;
+  }
+
+  bool operator()(const double& value) const {
+    return value == 0;
+  }
+
+  bool operator()(const bool& value) const {
+    return !value;
+  }
+
+  bool operator()(const std::string& value) const {
+    return value == "";
+  }
+
+  bool operator()(const array& array) const {
+    return array.size() == 0;
+  }
+};
+
+}