Just some cosmetics.

example/animal.c

@@ -38,8 +38,8 @@
  */
 static char *dupstr(const char *text)
 {
-    size_t  len;
-    char   *copy;
+    size_t len;
+    char *copy;
 
     if (!text)
         return NULL;

example/animal.h

@@ -38,10 +38,10 @@ struct AnimalVTable {
  * struct as their first member, which makes the upcast free.
  */
 struct Animal {
-    ooc_object          object;
+    ooc_object object;
     const AnimalVTable *vtable;
-    char               *name;
-    int                 age;
+    char *name;
+    int age;
 
     /*
      * Two fields that belong to the class alone, told apart by their leading
@@ -52,8 +52,8 @@ struct Animal {
      * nothing outside Animal can read or write it by name at all. Both are set
      * from the struct definition below, where the members are in view.
      */
-    int                 _id;
-    int                 __legs;
+    int _id;
+    int __legs;
 };
 
 /*

example/cat.c

@@ -43,8 +43,8 @@
  */
 static char *dupstr(const char *text)
 {
-    size_t  len;
-    char   *copy;
+    size_t len;
+    char *copy;
 
     if (!text)
         return NULL;
@@ -157,10 +157,10 @@ static const ooc_field Cat_fields[] = {
  * Dog stay distinguishable while both are passed around as Animal.
  */
 const ooc_class Cat_class = {
-    .size    = sizeof(Cat),
+    .size = sizeof(Cat),
     .destroy = destroy,
-    .super   = &Animal_class,
-    .fields  = Cat_fields,
+    .super = &Animal_class,
+    .fields = Cat_fields,
 };
 
 /*
@@ -203,8 +203,8 @@ Cat *cat_new(const char *name, int age, const char *colour)
     }
 
     cat->animal.vtable = &vt;
-    cat->colour        = dupstr(colour);
-    cat->_lives        = 9;
+    cat->colour = dupstr(colour);
+    cat->_lives = 9;
 
     if (!cat->colour) {
         ooc_release(cat);

example/cat.h

@@ -32,7 +32,7 @@ typedef struct Cat Cat;
  */
 struct Cat {
     Animal animal;
-    char  *colour;
+    char *colour;
 
     /*
      * Private to Cat, and readable by name: one leading underscore stops
@@ -40,7 +40,7 @@ struct Cat {
      * the same way, so the rule is the one in the library rather than something
      * the subclass has to repeat.
      */
-    int    _lives;
+    int _lives;
 };
 
 /*

example/dog.c

@@ -41,8 +41,8 @@
  */
 static char *dupstr(const char *text)
 {
-    size_t  len;
-    char   *copy;
+    size_t len;
+    char *copy;
 
     if (!text)
         return NULL;
@@ -128,7 +128,7 @@ static const AnimalVTable vt = {
  */
 static const ooc_field Dog_fields[] = {
     { "breed", offsetof(Dog, breed), sizeof(((Dog *)0)->breed), 1 },
-    { NULL,    0,                    0,                          0 },
+    { NULL,    0,                    0,                         0 },
 };
 
 /*
@@ -181,7 +181,7 @@ Dog *dog_new(const char *name, int age, const char *breed)
     }
 
     dog->animal.vtable = &vt;
-    dog->breed         = dupstr(breed);
+    dog->breed = dupstr(breed);
 
     if (!dog->breed) {
         ooc_release(dog);

example/dog.h

@@ -31,7 +31,7 @@ typedef struct Dog Dog;
  */
 struct Dog {
     Animal animal;
-    char  *breed;
+    char *breed;
 };
 
 /*