Coro::State			T_PTROBJ
Coro::State_or_hashref		T_STATE_OR_HASHREF

INPUT

T_STATE_OR_HASHREF
	{
           SV *arg = $arg;

           if (SvROK(arg) && SvTYPE(SvRV(arg)) == SVt_PVHV)
             {
               HE *he = hv_fetch_ent((HV *)SvRV(arg), ucoro_state_sv, 0, ucoro_state_hash);

               if (!he)
                 croak (\"${Package}::$func_name() -- $var is a hashref but lacks the \" UCORO_STATE \" key\");

               arg = HeVAL(he);
             }
              
           /* must also be changed inside Coro::Cont::yield */
           if (SvROK(arg) && SvSTASH(SvRV(arg)) == coro_state_stash)
             $var = ($type) SvIV((SV*)SvRV(arg));
           else
             croak (\"${Package}::$func_name() -- $var is not (and contains not) a Coro::State object\");
        }