thunk: double up THUNK() macro

this is necessary for nested THUNK() constructions, e.g.:

thunk_t * closure = THUNK(a, b, c, THUNK(d, e, f));

1 files changed, 4 insertions, 1 deletions

diff --git a/thunk.h b/thunk.h
index e4e4a08..dd80e84 100644
--- a/thunk.h
+++ b/thunk.h
@@ -416,9 +416,12 @@ struct thunk_t {
 
 /* Call the appropriate instantiate function which returns an embedded thunk_t,
  * this is how you prepare the thunks established via THUNK_DEFINE(). */
-#define THUNK(_call)								\
+#define _THUNK(_call)								\
 	__thunk_instantiate_##_call
 
+#define THUNK(_call)								\
+	_THUNK(_call)
+
 /* Call the function associated with a prepared thunk, supplying the bound environment
  * as arguments.  This is how code receiving generic thunks executes them. */
 static inline int thunk_dispatch(thunk_t *thunk) {