dep: Add rapidyaml

dep/rapidyaml/include/c4/yml/std/vector.hpp

@@ -0,0 +1,53 @@
+#ifndef _C4_YML_STD_VECTOR_HPP_
+#define _C4_YML_STD_VECTOR_HPP_
+
+#include "c4/yml/node.hpp"
+#include <c4/std/vector.hpp>
+#include <vector>
+
+namespace c4 {
+namespace yml {
+
+// vector is a sequence-like type, and it requires child nodes
+// in the data tree hierarchy (a SEQ node in ryml parlance).
+// So it should be serialized via write()/read().
+
+
+template<class V, class Alloc>
+void write(c4::yml::NodeRef *n, std::vector<V, Alloc> const& vec)
+{
+    *n |= c4::yml::SEQ;
+    for(auto const& v : vec)
+        n->append_child() << v;
+}
+
+template<class V, class Alloc>
+bool read(c4::yml::ConstNodeRef const& n, std::vector<V, Alloc> *vec)
+{
+    vec->resize(n.num_children());
+    size_t pos = 0;
+    for(auto const ch : n)
+        ch >> (*vec)[pos++];
+    return true;
+}
+
+/** specialization: std::vector<bool> uses std::vector<bool>::reference as
+ * the return value of its operator[]. */
+template<class Alloc>
+bool read(c4::yml::ConstNodeRef const& n, std::vector<bool, Alloc> *vec)
+{
+    vec->resize(n.num_children());
+    size_t pos = 0;
+    bool tmp;
+    for(auto const ch : n)
+    {
+        ch >> tmp;
+        (*vec)[pos++] = tmp;
+    }
+    return true;
+}
+
+} // namespace yml
+} // namespace c4
+
+#endif // _C4_YML_STD_VECTOR_HPP_