public function getConstraintString()

in src/Reflection/ReflectionXHPChildrenDeclaration.hack [129:140]


  public function getConstraintString(): string {
    $type = $this->getConstraintType();
    invariant(
      $type === XHPChildrenConstraintType::ELEMENT ||
        $type === XHPChildrenConstraintType::CATEGORY,
      'Only element and category constraints have string data - in %s',
      $this->context,
    );
    $data = $this->data[2];
    invariant($data is string, 'Expected string data');
    return $data;
  }