extern SCM scm_procedure_p SCM_P ((SCM obj));
extern SCM scm_closure_p SCM_P ((SCM obj));
extern SCM scm_thunk_p SCM_P ((SCM obj));
+extern SCM scm_procedure_documentation SCM_P ((SCM proc));
extern void scm_init_iprocs SCM_P ((scm_iproc *subra, int type));
extern void scm_init_procs SCM_P ((void));