Boolean	err;
bool	err;
assign_get_value(p, ctxt, err, endc)    const char 	**p;    SymTable 	*ctxt;    Boolean	err;    int		endc;{    const char *s;    int flags;    VarPattern *arg;    s = *p + 1;    if (s[0] == '=')    	flags = VAR_EQUAL;    else if (s[0] == '?' && s[1] == '=')    	flags = VAR_MAY_EQUAL;    else if (s[0] == '+' && s[1] == '=')    	flags = VAR_ADD_EQUAL;    else if (s[0] == '!' && s[1] == '=')    	flags = VAR_BANG_EQUAL;    else    	return NULL;    arg = get_value(&s, ctxt, err, endc);    if (arg != NULL) {    	*p = s;	arg->flags = flags;    }     return arg;}