/**
* Lookup which terminal symbols are permitted in a given state
*/
function permitted($state, Grammar $Grammar)
{
if (!isset($this->table[$state])) {
return array();
}
$all = array_keys($this->table[$state]);
//return $all;
$a = array();
foreach ($all as $t) {
if ($Grammar->is_terminal($t)) {
$a[] = $t;
}
}
return $a;
}
/**
* Collect siblings states including self.
* It is assumed that we only have one item at this point
* @param array reference to populate
* @return void
*/
function collect_states_passthru(&$states, Grammar $Grammar, array $excluded, $threadId)
{
if (isset($states[$this->id])) {
// recursion
return;
}
// check exclusions - These should only be passed when calling from a station,
// so we know there is only one item and it is at the beginning of the rule.
if ($excluded) {
$s = $this->Item->current_symbol();
if (in_array($s, $excluded, true)) {
//echo "Excluding state #$this->id because it begins with $s\n";
return;
}
if ($Grammar->is_terminal($s)) {
//echo "Clearing exclude list in state #$this->id for descent beyond $s\n";
$excluded = array();
}
//else {
// echo "Passing down ",count($excluded)," exclusions through state #$this->id \n";
//}
}
$states[$this->id] = $this;
foreach ($this->etransitions as $Station) {
$Station->collect_states_recursive($states, $Grammar, $excluded, $threadId);
}
}
