Add size function for maps

3 files changed, 32 insertions, 1 deletions

diff --git a/collections/map/map.adoc b/collections/map/map.adoc
index fc6b8b7..837a08a 100644
--- a/collections/map/map.adoc
+++ b/collections/map/map.adoc
@@ -1,7 +1,7 @@
 Map
 ===
 Tucker Evans
-v0.1, 2020-07-06
+v0.2, 2020-07-06
 
 A basic map implemented in an AVL tree.
 
@@ -50,3 +50,22 @@ Examples
 
 map *dict = map_new((cmp_func) strcmp);
 ----
+
+[[map_size]]
++map_size(map *self)+
+~~~~~~~~~~~~~~~~~~~~~
+Returns the number of key, value pairs stored in map +self+.
+
+Examples
+^^^^^^^^
+[source,c]
+----
+#include "map.h"
+#include <string.h>
+
+map *dict = map_new((cmp_func) strcmp);
+
+assert(map_size(dict) == 0);
+map_set(dict, "ONE", NULL);
+assert(map_size(dict) == 1);
+----
diff --git a/collections/map/map.c b/collections/map/map.c
index 803b5ad..712a895 100644
--- a/collections/map/map.c
+++ b/collections/map/map.c
@@ -25,3 +25,12 @@ cmp_func cmp;
 
 	return tmp;
 }
+
+int map_size(root)
+map *root;
+{
+	if (!root || !root->key)
+		return 0;
+
+	return map_size(root->left) + map_size(root->right) + 1;
+}
diff --git a/collections/map/map.h b/collections/map/map.h
index 8aad2f4..ef4b0c8 100644
--- a/collections/map/map.h
+++ b/collections/map/map.h
@@ -7,4 +7,7 @@ typedef int (*cmp_func)(void*, void*);
 /*constructors*/
 map* map_new(cmp_func);
 
+/*management*/
+int map_size(map*);
+
 #endif