EPNODE *
getchan(void) /* A -> $N = E1 */
{
EPNODE *ep1, *ep2;
if (nextc != '$')
syntax("missing '$'");
scan();
ep1 = newnode();
ep1->type = CHAN;
ep1->v.chan = getinum();
if (nextc != '=')
syntax("'=' expected");
scan();
ep2 = newnode();
ep2->type = '=';
addekid(ep2, ep1);
addekid(ep2, getE1());
return(ep2);
}
EPNODE *
getE5(void) /* E5 -> (E1) */
/* VAR */
/* NUM */
/* $N */
/* FUNC(E1,..) */
/* ARG */
{
int i;
char *nam;
EPNODE *ep1, *ep2;
if (nextc == '(') {
scan();
ep1 = getE1();
if (nextc != ')')
syntax("')' expected");
scan();
return(ep1);
}
if (esupport&E_INCHAN && nextc == '$') {
scan();
ep1 = newnode();
ep1->type = CHAN;
ep1->v.chan = getinum();
return(ep1);
}
if (esupport&(E_VARIABLE|E_FUNCTION) &&
(isalpha(nextc) || nextc == CNTXMARK)) {
nam = getname();
ep1 = NULL;
if ((esupport&(E_VARIABLE|E_FUNCTION)) == (E_VARIABLE|E_FUNCTION)
&& curfunc != NULL)
for (i = 1, ep2 = curfunc->v.kid->sibling;
ep2 != NULL; i++, ep2 = ep2->sibling)
if (!strcmp(ep2->v.name, nam)) {
ep1 = newnode();
ep1->type = ARG;
ep1->v.chan = i;
break;
}
if (ep1 == NULL) {
ep1 = newnode();
ep1->type = VAR;
ep1->v.ln = varinsert(nam);
}
if (esupport&E_FUNCTION && nextc == '(') {
ep2 = newnode();
ep2->type = FUNC;
addekid(ep2, ep1);
ep1 = ep2;
do {
scan();
addekid(ep1, getE1());
} while (nextc == ',');
if (nextc != ')')
syntax("')' expected");
scan();
} else if (!(esupport&E_VARIABLE))
syntax("'(' expected");
if (esupport&E_RCONST && isconstvar(ep1))
ep1 = rconst(ep1);
return(ep1);
}
if (isdecimal(nextc)) {
ep1 = newnode();
ep1->type = NUM;
ep1->v.num = getnum();
return(ep1);
}
syntax("unexpected character");
return NULL; /* pro forma return */
}