diff --git a/include/tr/interface/hashable.h b/include/tr/interface/hashable.h
index 116334e..898e4d0 100644
--- a/include/tr/interface/hashable.h
+++ b/include/tr/interface/hashable.h
@@ -34,8 +34,21 @@ TR_INTERFACE(TR_Hashable) {
 	fptr_TR_hashableHandleDouble handleDouble;
 };
 
-extern unsigned long TR_hashableGetHash(void *);
-extern void          TR_hashableHandleDouble(void *, void *);
+inline
+unsigned long
+TR_hashableGetHash(void * hashable)
+{
+	unsigned long ret;
+	TR_RETCALL(hashable, TR_Hashable, getHash, ret);
+	return ret;
+}
+
+inline
+void
+TR_hashableHandleDouble(void * hashable, void * new_hashable)
+{
+	TR_CALL(hashable, TR_Hashable, handleDouble, new_hashable);
+}
 
 #endif // __TR_INTERFACE_HASHABLE_H__
 
diff --git a/include/tr/interface/iterable.h b/include/tr/interface/iterable.h
index e74d5ca..0719283 100644
--- a/include/tr/interface/iterable.h
+++ b/include/tr/interface/iterable.h
@@ -42,10 +42,37 @@ TR_INTERFACE(TR_Iterable) {
 	TR_iterableRewind((this)); \
 	for (; TR_iterableValid((this)); TR_iterableNext((this)))
 
-extern void * TR_iterableCurrent(void *);
-extern void   TR_iterableNext(void *);
-extern void   TR_iterableRewind(void *);
-extern int    TR_iterableValid(void *);
+inline
+void *
+TR_iterableCurrent(void * iterable)
+{
+	void * ret;
+	TR_RETCALL(iterable, TR_Iterable, current, ret);
+	return ret;
+}
+
+inline
+void
+TR_iterableNext(void * iterable)
+{
+	TR_CALL(iterable, TR_Iterable, next);
+}
+
+inline
+void
+TR_iterableRewind(void * iterable)
+{
+	TR_CALL(iterable, TR_Iterable, rewind);
+}
+
+inline
+int
+TR_iterableValid(void * iterable)
+{
+	int ret;
+	TR_RETCALL(iterable, TR_Iterable, valid, ret);
+	return ret;
+}
 
 #endif // __TR_INTERFACE_ITERABLE_H__
 
diff --git a/src/hash/interface/hashable.c b/src/hash/interface/hashable.c
index 7de67da..68aa2f0 100644
--- a/src/hash/interface/hashable.c
+++ b/src/hash/interface/hashable.c
@@ -29,20 +29,7 @@
 
 TR_CREATE_INTERFACE(TR_Hashable, 2);
 
-unsigned long
-TR_hashableGetHash(void * hashable)
-{
-	unsigned long ret;
-
-	TR_RETCALL(hashable, TR_Hashable, getHash, ret);
-
-	return ret;
-}
-
-void
-TR_hashableHandleDouble(void * hashable, void * new_hashable)
-{
-	TR_CALL(hashable, TR_Hashable, handleDouble, new_hashable);
-}
+extern inline unsigned long TR_hashableGetHash(void *);
+extern inline void          TR_hashableHandleDouble(void *, void *);
 
 // vim: set ts=4 sw=4:
diff --git a/src/interface/iterable.c b/src/interface/iterable.c
index 1cfd086..55d9c7b 100644
--- a/src/interface/iterable.c
+++ b/src/interface/iterable.c
@@ -25,32 +25,9 @@
 
 TR_CREATE_INTERFACE(TR_Iterable, 4);
 
-void *
-TR_iterableCurrent(void * iterable)
-{
-	void * ret;
-	TR_RETCALL(iterable, TR_Iterable, current, ret);
-	return ret;
-}
-
-void
-TR_iterableNext(void * iterable)
-{
-	TR_CALL(iterable, TR_Iterable, next);
-}
-
-void
-TR_iterableRewind(void * iterable)
-{
-	TR_CALL(iterable, TR_Iterable, rewind);
-}
-
-int
-TR_iterableValid(void * iterable)
-{
-	int ret;
-	TR_RETCALL(iterable, TR_Iterable, valid, ret);
-	return ret;
-}
+extern inline void * TR_iterableCurrent(void *);
+extern inline void   TR_iterableNext(void *);
+extern inline void   TR_iterableRewind(void *);
+extern inline int    TR_iterableValid(void *);
 
 // vim: set ts=4 sw=4: