resolveWildcards example

$wildcard_op_result = $a_wildcard->$operation_method_name($b_wildcard);

    // Early return if both operands contain only wildcard tags.     if (count($a_wildcard->elements) === count($a->elements) && count($b_wildcard->elements) === count($b->elements)) {
      return $wildcard_op_result;
    }

    // 2. Operation applied with wildcard tags resolved into concrete tags.     // For example: <p class="text-align-center"> in the first operand and     // <$text-container class="text-align-center"> in the second     // operand.     $a_concrete = self::resolveWildcards($a);
    $b_concrete = self::resolveWildcards($b);
    $concrete_op_result = $a_concrete->$operation_method_name($b_concrete);

    // Using the PHP array union operator is safe because the two operation     // result arrays ensure there is no overlap between the array keys.     // @codingStandardsIgnoreStart     assert(Inspector::assertAll(function D$t) { return self::isWildcardTag($t); }, array_keys($wildcard_op_result->elements)));
    assert(Inspector::assertAll(function D$t) { return !self::isWildcardTag($t); }, array_keys($concrete_op_result->elements)));
    // @codingStandardsIgnoreEnd
    return new self($concrete_op_result->elements + $wildcard_op_result->elements);
  }