Index: doc/papers/OOPSLA17/evaluation/c-pair.h
===================================================================
--- doc/papers/OOPSLA17/evaluation/c-pair.h	(revision 90152a4860529aff7214be01cd22abd37012cd19)
+++ doc/papers/OOPSLA17/evaluation/c-pair.h	(revision 90152a4860529aff7214be01cd22abd37012cd19)
@@ -0,0 +1,16 @@
+#pragma once
+
+struct pair {
+	void* first;
+	void* second;
+};
+
+struct pair* new_pair(void* first, void* second);
+
+struct pair* copy_pair(const struct pair* src, 
+	void* (*copy_first)(const void*), void* (*copy_second)(const void*));
+
+void free_pair(struct pair* p, void (*free_first)(void*), void (*free_second)(void*));
+
+int cmp_pair(const struct pair* a, const struct pair* b, 
+	int (*cmp_first)(const void*, const void*), int (*cmp_second)(const void*, const void*));