libBLOC

diff --git a/include/BLOC/object.h b/include/BLOC/object.h
index 9c221f5..64d685c 100644
--- a/include/BLOC/object.h
+++ b/include/BLOC/object.h
@@ -33,10 +33,12 @@ struct ObjectType {
 	void (*delete)(void *);
 };
 
+int obj_verify(void *addr);
 unsigned int obj_usage(void *addr);
 void *obj_get(void *addr);
 void obj_put(void *addr);
 void *obj_new(struct ObjectType *type);
+struct ObjectType *obj_type(void *addr);
 
 #define obj_drop(v) ({ obj_put(v); v = NULL; })
 #define obj_swap(v,o) ({ obj_put(v); v = obj_get(o); })
diff --git a/iterator/iterator_relative.c b/iterator/iterator_relative.c
index d719718..0a6b962 100644
--- a/iterator/iterator_relative.c
+++ b/iterator/iterator_relative.c
@@ -34,7 +34,7 @@ iterator_next(Iterator *iter)
 	return iter->entry->obj;
 }
 
-/* Get the prev iterable element */
+/* Get the previous iterable element */
 void *
 iterator_prev(Iterator *iter)
 {
diff --git a/list/list.c b/list/list.c
index 888ff12..c5ff224 100644
--- a/list/list.c
+++ b/list/list.c
@@ -19,7 +19,7 @@
 
 /*
  * This file implements object Lists.  Objects can be a part of multiple lists
- * that can be managed automatically by the library.  This prevents subsystems
+ * that can be managed automatically by the library.  This prevents programs
  * from having to implement their own object lists for sub-objects. Lists may
  * be created with a specific Object Type, and will not accept objects that are
  * not of that type.  If a list does not have a type, it will accept objects of
@@ -29,7 +29,6 @@
 #include <BLOC/object.h>
 #include <BLOC/list.h>
 #include "../assert.h"
-#include "../object.h"
 #include "list.h"
 
 static void _list_new(void *);
diff --git a/list/list_add.c b/list/list_add.c
index 276a158..ad5ddec 100644
--- a/list/list_add.c
+++ b/list/list_add.c
@@ -20,7 +20,6 @@
 #include <BLOC/object.h>
 #include <BLOC/list.h>
 #include "../assert.h"
-#include "../object.h"
 #include "list.h"
 
 /* Add an object to a list */
@@ -29,9 +28,8 @@ list_add(List *list, void *obj)
 {
 	ASSERT(list);
 	ASSERT(obj);
-	struct ObjectHeader *header = object_header(obj);
-	ASSERT(header->magic == OBJECT_MAGIC);
-	if (list->type && list->type != header->type)
+	ASSERT(obj_verify(obj));
+	if (list->type && list->type != obj_type(obj))
 		return;
 
 	struct IterableEntry *entry;
diff --git a/list/list_remove.c b/list/list_remove.c
index 767fb09..8aeac63 100644
--- a/list/list_remove.c
+++ b/list/list_remove.c
@@ -20,7 +20,6 @@
 #include <BLOC/object.h>
 #include <BLOC/list.h>
 #include "../assert.h"
-#include "../object.h"
 #include "list.h"
 
 /* Remove an object from a list */
@@ -29,11 +28,10 @@ list_remove(List *list, void *obj)
 {
 	ASSERT(list);
 	ASSERT(obj);
-	struct ObjectHeader *header = object_header(obj);
-	ASSERT(header->magic == OBJECT_MAGIC);
+	ASSERT(obj_verify(obj));
 	if (!list->header.start)
 		return;
-	if (list->type && list->type != header->type)
+	if (list->type && list->type != obj_type(obj))
 		return;
 	obj_lock(list);
 
diff --git a/object.c b/object.c
index f51dbbd..52fbe89 100644
--- a/object.c
+++ b/object.c
@@ -33,11 +33,20 @@
 #include "../assert.h"
 #include "object.h"
 
-/* Count the number of reference an object has */
+/* Verify that a pointer points to a valid object */
+int
+obj_verify(void *addr)
+{
+	struct ObjectHeader *obj = object_header(addr);
+	return (int) (obj->magic == OBJECT_MAGIC);
+}
+
+/* Count the number of references an object has */
 unsigned int
 obj_usage(void *addr)
 {
 	struct ObjectHeader *obj = object_header(addr);
+	ASSERT(obj->magic == OBJECT_MAGIC);
 	return (unsigned int) obj->usage;
 }
 
@@ -89,6 +98,15 @@ obj_new(struct ObjectType *type)
 	return obj_get(body);
 }
 
+/* Return the object type of an object */
+struct ObjectType *
+obj_type(void *addr)
+{
+	struct ObjectHeader *obj = object_header(addr);
+	ASSERT(obj->magic == OBJECT_MAGIC);
+	return obj->type;
+}
+
 /* Lock an object */
 void
 obj_lock(void *addr)
diff --git a/tree/tree.c b/tree/tree.c
index 1bffd72..6e23c5a 100644
--- a/tree/tree.c
+++ b/tree/tree.c
@@ -28,7 +28,6 @@
 #include <BLOC/object.h>
 #include <BLOC/tree.h>
 #include "../assert.h"
-#include "../object.h"
 #include "tree.h"
 
 static void _tree_new(void *);
diff --git a/tree/tree_add.c b/tree/tree_add.c
index 67397ba..bca8c7e 100644
--- a/tree/tree_add.c
+++ b/tree/tree_add.c
@@ -20,7 +20,6 @@
 #include <BLOC/object.h>
 #include <BLOC/tree.h>
 #include "../assert.h"
-#include "../object.h"
 #include "tree.h"
 
 /* Add a node to a tree recursively */
@@ -72,9 +71,8 @@ tree_add(Tree *tree, void *obj)
 {
 	ASSERT(tree);
 	ASSERT(obj);
-	struct ObjectHeader *header = object_header(obj);
-	ASSERT(header->magic == OBJECT_MAGIC);
-	if (tree->type && tree->type != header->type)
+	ASSERT(obj_verify(obj));
+	if (tree->type && tree->type != obj_type(obj))
 		return;
 
 	struct TreeNode *node;
diff --git a/tree/tree_remove.c b/tree/tree_remove.c
index 6510a03..6f1ad90 100644
--- a/tree/tree_remove.c
+++ b/tree/tree_remove.c
@@ -48,7 +48,7 @@ _tree_remove_r(Tree *t, struct TreeNode *parent, struct TreeNode *child)
 	} else if (t->compare(parent->header.obj, child->header.obj) < 0) {
 		parent->right = _tree_remove_r(t, parent->right, child);
 	} else {
-		/* Less that two children: adopt child if available */
+		/* Less than two children: adopt child if available */
 		if (!child->left)
 			return child->right;
 		if (!child->right)
@@ -75,11 +75,10 @@ tree_remove(Tree *tree, void *obj)
 {
 	ASSERT(tree);
 	ASSERT(obj);
-	struct ObjectHeader *header = object_header(obj);
-	ASSERT(header->magic == OBJECT_MAGIC);
+	ASSERT(obj_verify(obj));
 	if (!tree->header.start)
 		return;
-	if (tree->type && tree->type != header->type)
+	if (tree->type && tree->type != obj_type(obj))
 		return;
 	obj_lock(tree);
 
@@ -93,7 +92,7 @@ tree_remove(Tree *tree, void *obj)
 	/* Unlink from tree */
 	tree->root = _tree_remove_r(tree, tree->root, node);
 
-	/* Unlink from linear list*/
+	/* Unlink from linear list */
 	if (tree->header.start == &node->header)
 		tree->header.start = node->header.next;
 	if (tree->header.end == &node->header)