move pic_env to proc.h

include/picrin.h

@@ -7,11 +7,6 @@
 #include "picconf.h"
 #include "picrin/value.h"
 
-struct pic_env {
-  pic_value assoc;
-  struct pic_env *parent;
-};
-
 typedef struct {
   pic_value *sp;
   pic_value *stbase, *stend;

include/picrin/proc.h

@@ -1,6 +1,11 @@
 #ifndef PROC_H__
 #define PROC_H__
 
+struct pic_env {
+  pic_value assoc;
+  struct pic_env *parent;
+};
+
 struct pic_proc {
   PIC_OBJECT_HEADER
   bool cfunc_p;

src/state.c

@@ -2,6 +2,7 @@
 
 #include "picrin.h"
 #include "picrin/gc.h"
+#include "picrin/proc.h"
 
 static struct pic_env *
 pic_new_empty_env()