本文整理汇总了PHP中Term::getInstances方法的典型用法代码示例。如果您正苦于以下问题：PHP Term::getInstances方法的具体用法？PHP Term::getInstances怎么用？PHP Term::getInstances使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类Term的用法示例。
在下文中一共展示了Term::getInstances方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的PHP代码示例。
示例1: eval_term
private function eval_term(Term $term)
{
$rel = $term->getName();
$vars = $term->getVariables();
// $vars: [Variable]
// all variables have value, no need to generate/iterate candidates
if ($term->readyForResolve()) {
return $this->isTrue($rel, $term->getInstances());
}
/* ---------Have to fill the variables with a candidate value ----------- */
try {
if ($this->isRule($rel)) {
$candidates = $this->instance_generator_for_rule($term);
} else {
$candidates = $this->instance_generator_for_fact($term);
}
} catch (Exception $e) {
//echo "no candidates for: \n"; echo " " . $term->toString() . "\n";
return FALSE;
}
foreach ($candidates as $_instances) {
//echo $term->toString() . "\n";
//print_r($_instances);
$term->assignValues($_instances);
// if $term is fact, isTrue() will not assign value for
// variables, it could make wrong variable value for next
// term. for example:
// hasDesc(A, C) :- hasChild(A, B) o hasDesc(A, C)
// assign A = 'x', C = 'z'
// hasDesc('x', 'z') :- hasChild('x', ?) o hasDesc(?, 'z')
// assign ? = 'y'
// hasDesc('x', 'z') :- hasChild('x', 'y') o hasDesc('y', 'z')
// if we don't assigin value to ?
// hasDesc(?, 'z') will be evaulated
// the candicate of ? could be ['x', 'y', 'z'], then
// hasDesc('x', 'z') cause infinite loop
if ($this->isTrue($rel, $_instances)) {
// recursive eval next, if return true, return true
// if next term false, continue the iteration
if (NULL == $term->next()) {
return TRUE;
}
// no more for eval
if ($this->eval_term($term->next())) {
return TRUE;
}
}
}
return FALSE;
// all candidate are false.
}