Comment a little bit more the examples

example/ex-array05.c

@@ -4,12 +4,14 @@
 /* This example show how to use complex structure with array 
    embedding another library */
 
-/* This is a trivial library */
+/* This is a typical trivial library with its interface */
 typedef struct lib_ext_struct {
   int id;
-  // Other data
+  // Other data may be added
 } lib_ext_struct;
 
+/* Method to create a duplicate of the object.
+   The new object is heap allocated */
 static lib_ext_struct *lib_ext_struct_Duplicate(const lib_ext_struct *obj)
 {
   lib_ext_struct *p = malloc(sizeof(lib_ext_struct));
@@ -18,6 +20,7 @@ static lib_ext_struct *lib_ext_struct_Duplicate(const lib_ext_struct *obj)
   return p;
 }
 
+/* Method to delete any object */
 static void lib_ext_struct_Delete(lib_ext_struct *obj)
 {
   free(obj);
@@ -101,11 +104,12 @@ ARRAY_DEF(/* the array prefix */ array_data_node,
 				   INIT_SET(API_6(data_node_init_set)),
 				   CLEAR(API_2(data_node_clear))))
 
-/* Define a global array */
+/* Define a global array with the created type */
 array_data_node_t global_array;
 
 int main(void)
 {
+  /* Call the created method */
   array_data_node_init(global_array);
   /* Do stuff... */
   array_data_node_clear(global_array);

example/ex-rbtree01.c

@@ -4,6 +4,15 @@
 
 #include "m-rbtree.h"
 
+// Let's define one utility function.
+void *xmalloc(size_t n);
+void *xmalloc(size_t n)
+{
+  void *p = malloc (n);
+  if (!p) abort();
+  return p;
+}
+
 // Let's define a new type.
 typedef struct {
   int  key;
@@ -12,7 +21,7 @@ typedef struct {
 
 #define SIZE 256
 
-void *xmalloc(size_t n);
+// Let's define the prototypes of the methods of this new type.
 void my_type_init(my_type_t x);
 void my_type_clear(my_type_t x);
 void my_type_init_set(my_type_t x, const my_type_t y);
@@ -24,13 +33,6 @@ void my_type_out_str(FILE *f, const my_type_t x);
 bool my_type_in_str(my_type_t x, FILE *f);
 void my_type_rand(my_type_t x);
 
-void *xmalloc(size_t n)
-{
-  void *p = malloc (n);
-  if (!p) abort();
-  return p;
-}
-
 // Let's define its constructor
 void my_type_init(my_type_t x)
 {