final class DocParser

DocParserTest.php in drupal/core/vendor/doctrine/common/tests/Doctrine/Tests/Common/Annotations/DocParserTest.php

PerformanceTest.php in drupal/core/vendor/doctrine/common/tests/Doctrine/Tests/Common/Annotations/PerformanceTest.php

final class DocParser {

  /**
   * An array of all valid tokens for a class name.
   *
   * @var array
   */
  private static $classIdentifiers = array(
    DocLexer::T_IDENTIFIER,
    DocLexer::T_TRUE,
    DocLexer::T_FALSE,
    DocLexer::T_NULL,
  );

  /**
   * The lexer.
   *
   * @var \Doctrine\Common\Annotations\DocLexer
   */
  private $lexer;

  /**
   * Current target context
   *
   * @var string
   */
  private $target;

  /**
   * Doc Parser used to collect annotation target
   *
   * @var \Doctrine\Common\Annotations\DocParser
   */
  private static $metadataParser;

  /**
   * Flag to control if the current annotation is nested or not.
   *
   * @var boolean
   */
  private $isNestedAnnotation = false;

  /**
   * Hashmap containing all use-statements that are to be used when parsing
   * the given doc block.
   *
   * @var array
   */
  private $imports = array();

  /**
   * This hashmap is used internally to cache results of class_exists()
   * look-ups.
   *
   * @var array
   */
  private $classExists = array();

  /**
   * Whether annotations that have not been imported should be ignored.
   *
   * @var boolean
   */
  private $ignoreNotImportedAnnotations = false;

  /**
   * An array of default namespaces if operating in simple mode.
   *
   * @var array
   */
  private $namespaces = array();

  /**
   * A list with annotations that are not causing exceptions when not resolved to an annotation class.
   *
   * The names must be the raw names as used in the class, not the fully qualified
   * class names.
   *
   * @var array
   */
  private $ignoredAnnotationNames = array();

  /**
   * @var string
   */
  private $context = '';

  /**
   * Hash-map for caching annotation metadata
   * @var array
   */
  private static $annotationMetadata = array(
    'Doctrine\\Common\\Annotations\\Annotation\\Target' => array(
      'is_annotation' => true,
      'has_constructor' => true,
      'properties' => array(),
      'targets_literal' => 'ANNOTATION_CLASS',
      'targets' => Target::TARGET_CLASS,
      'default_property' => 'value',
      'attribute_types' => array(
        'value' => array(
          'required' => false,
          'type' => 'array',
          'array_type' => 'string',
          'value' => 'array<string>',
        ),
      ),
    ),
    'Doctrine\\Common\\Annotations\\Annotation\\Attribute' => array(
      'is_annotation' => true,
      'has_constructor' => false,
      'targets_literal' => 'ANNOTATION_ANNOTATION',
      'targets' => Target::TARGET_ANNOTATION,
      'default_property' => 'name',
      'properties' => array(
        'name' => 'name',
        'type' => 'type',
        'required' => 'required',
      ),
      'attribute_types' => array(
        'value' => array(
          'required' => true,
          'type' => 'string',
          'value' => 'string',
        ),
        'type' => array(
          'required' => true,
          'type' => 'string',
          'value' => 'string',
        ),
        'required' => array(
          'required' => false,
          'type' => 'boolean',
          'value' => 'boolean',
        ),
      ),
    ),
    'Doctrine\\Common\\Annotations\\Annotation\\Attributes' => array(
      'is_annotation' => true,
      'has_constructor' => false,
      'targets_literal' => 'ANNOTATION_CLASS',
      'targets' => Target::TARGET_CLASS,
      'default_property' => 'value',
      'properties' => array(
        'value' => 'value',
      ),
      'attribute_types' => array(
        'value' => array(
          'type' => 'array',
          'required' => true,
          'array_type' => 'Doctrine\\Common\\Annotations\\Annotation\\Attribute',
          'value' => 'array<Doctrine\\Common\\Annotations\\Annotation\\Attribute>',
        ),
      ),
    ),
  );

  /**
   * Hash-map for handle types declaration
   *
   * @var array
   */
  private static $typeMap = array(
    'float' => 'double',
    'bool' => 'boolean',
    // allow uppercase Boolean in honor of George Boole
    'Boolean' => 'boolean',
    'int' => 'integer',
  );

  /**
   * Constructs a new DocParser.
   */
  public function __construct() {
    $this->lexer = new DocLexer();
  }

  /**
   * Sets the annotation names that are ignored during the parsing process.
   *
   * The names are supposed to be the raw names as used in the class, not the
   * fully qualified class names.
   *
   * @param array $names
   */
  public function setIgnoredAnnotationNames(array $names) {
    $this->ignoredAnnotationNames = $names;
  }

  /**
   * Sets ignore on not-imported annotations
   *
   * @param $bool
   */
  public function setIgnoreNotImportedAnnotations($bool) {
    $this->ignoreNotImportedAnnotations = (bool) $bool;
  }

  /**
   * Sets the default namespaces.
   *
   * @param array $namespace
   *
   * @throws \RuntimeException
   */
  public function addNamespace($namespace) {
    if ($this->imports) {
      throw new \RuntimeException('You must either use addNamespace(), or setImports(), but not both.');
    }
    $this->namespaces[] = $namespace;
  }

  /**
   * Sets the imports
   *
   * @param array $imports
   * @throws \RuntimeException
   */
  public function setImports(array $imports) {
    if ($this->namespaces) {
      throw new \RuntimeException('You must either use addNamespace(), or setImports(), but not both.');
    }
    $this->imports = $imports;
  }

  /**
   * Sets current target context as bitmask.
   *
   * @param integer $target
   */
  public function setTarget($target) {
    $this->target = $target;
  }

  /**
   * Parses the given docblock string for annotations.
   *
   * @param string $input The docblock string to parse.
   * @param string $context The parsing context.
   * @return array Array of annotations. If no annotations are found, an empty array is returned.
   */
  public function parse($input, $context = '') {
    if (false === ($pos = strpos($input, '@'))) {
      return array();
    }

    // also parse whatever character is before the @
    if ($pos > 0) {
      $pos -= 1;
    }
    $this->context = $context;
    $this->lexer
      ->setInput(trim(substr($input, $pos), '* /'));
    $this->lexer
      ->moveNext();
    return $this
      ->Annotations();
  }

  /**
   * Attempts to match the given token with the current lookahead token.
   * If they match, updates the lookahead token; otherwise raises a syntax error.
   *
   * @param int $token type of Token.
   * @return bool True if tokens match; false otherwise.
   */
  private function match($token) {
    if (!$this->lexer
      ->isNextToken($token)) {
      $this
        ->syntaxError($this->lexer
        ->getLiteral($token));
    }
    return $this->lexer
      ->moveNext();
  }

  /**
   * Attempts to match the current lookahead token with any of the given tokens.
   *
   * If any of them matches, this method updates the lookahead token; otherwise
   * a syntax error is raised.
   *
   * @param array $tokens
   * @return bool
   */
  private function matchAny(array $tokens) {
    if (!$this->lexer
      ->isNextTokenAny($tokens)) {
      $this
        ->syntaxError(implode(' or ', array_map(array(
        $this->lexer,
        'getLiteral',
      ), $tokens)));
    }
    return $this->lexer
      ->moveNext();
  }

  /**
   * Generates a new syntax error.
   *
   * @param string $expected Expected string.
   * @param array $token Optional token.
   *
   * @throws AnnotationException
   */
  private function syntaxError($expected, $token = null) {
    if ($token === null) {
      $token = $this->lexer->lookahead;
    }
    $message = "Expected {$expected}, got ";
    if ($this->lexer->lookahead === null) {
      $message .= 'end of string';
    }
    else {
      $message .= "'{$token['value']}' at position {$token['position']}";
    }
    if (strlen($this->context)) {
      $message .= ' in ' . $this->context;
    }
    $message .= '.';
    throw AnnotationException::syntaxError($message);
  }

  /**
   * Attempt to check if a class exists or not. This never goes through the PHP autoloading mechanism
   * but uses the {@link AnnotationRegistry} to load classes.
   *
   * @param string $fqcn
   * @return boolean
   */
  private function classExists($fqcn) {
    if (isset($this->classExists[$fqcn])) {
      return $this->classExists[$fqcn];
    }

    // first check if the class already exists, maybe loaded through another AnnotationReader
    if (class_exists($fqcn, false)) {
      return $this->classExists[$fqcn] = true;
    }

    // final check, does this class exist?
    return $this->classExists[$fqcn] = AnnotationRegistry::loadAnnotationClass($fqcn);
  }

  /**
   * Collects parsing metadata for a given annotation class
   *
   * @param string $name The annotation name
   */
  private function collectAnnotationMetadata($name) {
    if (self::$metadataParser == null) {
      self::$metadataParser = new self();
      self::$metadataParser
        ->setTarget(Target::TARGET_CLASS);
      self::$metadataParser
        ->setIgnoreNotImportedAnnotations(true);
      self::$metadataParser
        ->setImports(array(
        'target' => 'Doctrine\\Common\\Annotations\\Annotation\\Target',
        'attribute' => 'Doctrine\\Common\\Annotations\\Annotation\\Attribute',
        'attributes' => 'Doctrine\\Common\\Annotations\\Annotation\\Attributes',
      ));
      AnnotationRegistry::registerFile(__DIR__ . '/Annotation/Target.php');
      AnnotationRegistry::registerFile(__DIR__ . '/Annotation/Attribute.php');
      AnnotationRegistry::registerFile(__DIR__ . '/Annotation/Attributes.php');
    }
    $class = new \ReflectionClass($name);
    $docComment = $class
      ->getDocComment();

    // Sets default values for annotation metadata
    $metadata = array(
      'default_property' => null,
      'has_constructor' => null !== ($constructor = $class
        ->getConstructor()) && $constructor
        ->getNumberOfParameters() > 0,
      'properties' => array(),
      'property_types' => array(),
      'attribute_types' => array(),
      'targets_literal' => null,
      'targets' => Target::TARGET_ALL,
      'is_annotation' => false !== strpos($docComment, '@Annotation'),
    );

    // verify that the class is really meant to be an annotation
    if ($metadata['is_annotation']) {
      foreach (self::$metadataParser
        ->parse($docComment, 'class @' . $name) as $annotation) {
        if ($annotation instanceof Target) {
          $metadata['targets'] = $annotation->targets;
          $metadata['targets_literal'] = $annotation->literal;
        }
        elseif ($annotation instanceof Attributes) {
          foreach ($annotation->value as $attrib) {

            // handle internal type declaration
            $type = isset(self::$typeMap[$attrib->type]) ? self::$typeMap[$attrib->type] : $attrib->type;

            // handle the case if the property type is mixed
            if ('mixed' !== $type) {

              // Checks if the property has array<type>
              if (false !== ($pos = strpos($type, '<'))) {
                $arrayType = substr($type, $pos + 1, -1);
                $type = 'array';
                if (isset(self::$typeMap[$arrayType])) {
                  $arrayType = self::$typeMap[$arrayType];
                }
                $metadata['attribute_types'][$attrib->name]['array_type'] = $arrayType;
              }
              $metadata['attribute_types'][$attrib->name]['type'] = $type;
              $metadata['attribute_types'][$attrib->name]['value'] = $attrib->type;
              $metadata['attribute_types'][$attrib->name]['required'] = $attrib->required;
            }
          }
        }
      }

      // if not has a constructor will inject values into public properties
      if (false === $metadata['has_constructor']) {

        // collect all public properties
        foreach ($class
          ->getProperties(\ReflectionProperty::IS_PUBLIC) as $property) {
          $metadata['properties'][$property->name] = $property->name;

          // checks if the property has @var annotation
          if (false !== ($propertyComment = $property
            ->getDocComment()) && false !== strpos($propertyComment, '@var') && preg_match('/@var\\s+([^\\s]+)/', $propertyComment, $matches)) {

            // literal type declaration
            $value = $matches[1];

            // handle internal type declaration
            $type = isset(self::$typeMap[$value]) ? self::$typeMap[$value] : $value;

            // handle the case if the property type is mixed
            if ('mixed' !== $type) {

              // Checks if the property has @var array<type> annotation
              if (false !== ($pos = strpos($type, '<'))) {
                $arrayType = substr($type, $pos + 1, -1);
                $type = 'array';
                if (isset(self::$typeMap[$arrayType])) {
                  $arrayType = self::$typeMap[$arrayType];
                }
                $metadata['attribute_types'][$property->name]['array_type'] = $arrayType;
              }
              $metadata['attribute_types'][$property->name]['type'] = $type;
              $metadata['attribute_types'][$property->name]['value'] = $value;
              $metadata['attribute_types'][$property->name]['required'] = false !== strpos($propertyComment, '@Required');
            }
          }
        }

        // choose the first property as default property
        $metadata['default_property'] = reset($metadata['properties']);
      }
    }
    self::$annotationMetadata[$name] = $metadata;
  }

  /**
   * Annotations ::= Annotation {[ "*" ]* [Annotation]}*
   *
   * @return array
   */
  private function Annotations() {
    $annotations = array();
    while (null !== $this->lexer->lookahead) {
      if (DocLexer::T_AT !== $this->lexer->lookahead['type']) {
        $this->lexer
          ->moveNext();
        continue;
      }

      // make sure the @ is preceded by non-catchable pattern
      if (null !== $this->lexer->token && $this->lexer->lookahead['position'] === $this->lexer->token['position'] + strlen($this->lexer->token['value'])) {
        $this->lexer
          ->moveNext();
        continue;
      }

      // make sure the @ is followed by either a namespace separator, or
      // an identifier token
      if (null === ($peek = $this->lexer
        ->glimpse()) || DocLexer::T_NAMESPACE_SEPARATOR !== $peek['type'] && !in_array($peek['type'], self::$classIdentifiers, true) || $peek['position'] !== $this->lexer->lookahead['position'] + 1) {
        $this->lexer
          ->moveNext();
        continue;
      }
      $this->isNestedAnnotation = false;
      if (false !== ($annot = $this
        ->Annotation())) {
        $annotations[] = $annot;
      }
    }
    return $annotations;
  }

  /**
   * Annotation     ::= "@" AnnotationName ["(" [Values] ")"]
   * AnnotationName ::= QualifiedName | SimpleName
   * QualifiedName  ::= NameSpacePart "\" {NameSpacePart "\"}* SimpleName
   * NameSpacePart  ::= identifier | null | false | true
   * SimpleName     ::= identifier | null | false | true
   *
   * @throws AnnotationException
   * @return mixed False if it is not a valid annotation.
   */
  private function Annotation() {
    $this
      ->match(DocLexer::T_AT);

    // check if we have an annotation
    $name = $this
      ->Identifier();

    // only process names which are not fully qualified, yet
    // fully qualified names must start with a \
    $originalName = $name;
    if ('\\' !== $name[0]) {
      $alias = false === ($pos = strpos($name, '\\')) ? $name : substr($name, 0, $pos);
      $found = false;
      if ($this->namespaces) {
        foreach ($this->namespaces as $namespace) {
          if ($this
            ->classExists($namespace . '\\' . $name)) {
            $name = $namespace . '\\' . $name;
            $found = true;
            break;
          }
        }
      }
      elseif (isset($this->imports[$loweredAlias = strtolower($alias)])) {
        if (false !== $pos) {
          $name = $this->imports[$loweredAlias] . substr($name, $pos);
        }
        else {
          $name = $this->imports[$loweredAlias];
        }
        $found = true;
      }
      elseif (isset($this->imports['__NAMESPACE__']) && $this
        ->classExists($this->imports['__NAMESPACE__'] . '\\' . $name)) {
        $name = $this->imports['__NAMESPACE__'] . '\\' . $name;
        $found = true;
      }
      elseif ($this
        ->classExists($name)) {
        $found = true;
      }
      if (!$found) {
        if ($this->ignoreNotImportedAnnotations || isset($this->ignoredAnnotationNames[$name])) {
          return false;
        }
        throw AnnotationException::semanticalError(sprintf('The annotation "@%s" in %s was never imported. Did you maybe forget to add a "use" statement for this annotation?', $name, $this->context));
      }
    }
    if (!$this
      ->classExists($name)) {
      throw AnnotationException::semanticalError(sprintf('The annotation "@%s" in %s does not exist, or could not be auto-loaded.', $name, $this->context));
    }

    // at this point, $name contains the fully qualified class name of the
    // annotation, and it is also guaranteed that this class exists, and
    // that it is loaded
    // collects the metadata annotation only if there is not yet
    if (!isset(self::$annotationMetadata[$name])) {
      $this
        ->collectAnnotationMetadata($name);
    }

    // verify that the class is really meant to be an annotation and not just any ordinary class
    if (self::$annotationMetadata[$name]['is_annotation'] === false) {
      if (isset($this->ignoredAnnotationNames[$originalName])) {
        return false;
      }
      throw AnnotationException::semanticalError(sprintf('The class "%s" is not annotated with @Annotation. Are you sure this class can be used as annotation? If so, then you need to add @Annotation to the _class_ doc comment of "%s". If it is indeed no annotation, then you need to add @IgnoreAnnotation("%s") to the _class_ doc comment of %s.', $name, $name, $originalName, $this->context));
    }

    //if target is nested annotation
    $target = $this->isNestedAnnotation ? Target::TARGET_ANNOTATION : $this->target;

    // Next will be nested
    $this->isNestedAnnotation = true;

    //if annotation does not support current target
    if (0 === (self::$annotationMetadata[$name]['targets'] & $target) && $target) {
      throw AnnotationException::semanticalError(sprintf('Annotation @%s is not allowed to be declared on %s. You may only use this annotation on these code elements: %s.', $originalName, $this->context, self::$annotationMetadata[$name]['targets_literal']));
    }
    $values = array();
    if ($this->lexer
      ->isNextToken(DocLexer::T_OPEN_PARENTHESIS)) {
      $this
        ->match(DocLexer::T_OPEN_PARENTHESIS);
      if (!$this->lexer
        ->isNextToken(DocLexer::T_CLOSE_PARENTHESIS)) {
        $values = $this
          ->Values();
      }
      $this
        ->match(DocLexer::T_CLOSE_PARENTHESIS);
    }

    // checks all declared attributes
    foreach (self::$annotationMetadata[$name]['attribute_types'] as $property => $type) {
      if ($property === self::$annotationMetadata[$name]['default_property'] && !isset($values[$property]) && isset($values['value'])) {
        $property = 'value';
      }

      // handle a not given attribute or null value
      if (!isset($values[$property])) {
        if ($type['required']) {
          throw AnnotationException::requiredError($property, $originalName, $this->context, 'a(n) ' . $type['value']);
        }
        continue;
      }
      if ($type['type'] === 'array') {

        // handle the case of a single value
        if (!is_array($values[$property])) {
          $values[$property] = array(
            $values[$property],
          );
        }

        // checks if the attribute has array type declaration, such as "array<string>"
        if (isset($type['array_type'])) {
          foreach ($values[$property] as $item) {
            if (gettype($item) !== $type['array_type'] && !$item instanceof $type['array_type']) {
              throw AnnotationException::typeError($property, $originalName, $this->context, 'either a(n) ' . $type['array_type'] . ', or an array of ' . $type['array_type'] . 's', $item);
            }
          }
        }
      }
      elseif (gettype($values[$property]) !== $type['type'] && !$values[$property] instanceof $type['type']) {
        throw AnnotationException::typeError($property, $originalName, $this->context, 'a(n) ' . $type['value'], $values[$property]);
      }
    }

    // check if the annotation expects values via the constructor,
    // or directly injected into public properties
    if (self::$annotationMetadata[$name]['has_constructor'] === true) {
      return new $name($values);
    }
    $instance = new $name();
    foreach ($values as $property => $value) {
      if (!isset(self::$annotationMetadata[$name]['properties'][$property])) {
        if ('value' !== $property) {
          throw AnnotationException::creationError(sprintf('The annotation @%s declared on %s does not have a property named "%s". Available properties: %s', $originalName, $this->context, $property, implode(', ', self::$annotationMetadata[$name]['properties'])));
        }

        // handle the case if the property has no annotations
        if (!($property = self::$annotationMetadata[$name]['default_property'])) {
          throw AnnotationException::creationError(sprintf('The annotation @%s declared on %s does not accept any values, but got %s.', $originalName, $this->context, json_encode($values)));
        }
      }
      $instance->{$property} = $value;
    }
    return $instance;
  }

  /**
   * Values ::= Array | Value {"," Value}*
   *
   * @return array
   */
  private function Values() {
    $values = array();

    // Handle the case of a single array as value, i.e. @Foo({....})
    if ($this->lexer
      ->isNextToken(DocLexer::T_OPEN_CURLY_BRACES)) {
      $values['value'] = $this
        ->Value();
      return $values;
    }
    $values[] = $this
      ->Value();
    while ($this->lexer
      ->isNextToken(DocLexer::T_COMMA)) {
      $this
        ->match(DocLexer::T_COMMA);
      $token = $this->lexer->lookahead;
      $value = $this
        ->Value();
      if (!is_object($value) && !is_array($value)) {
        $this
          ->syntaxError('Value', $token);
      }
      $values[] = $value;
    }
    foreach ($values as $k => $value) {
      if (is_object($value) && $value instanceof \stdClass) {
        $values[$value->name] = $value->value;
      }
      else {
        if (!isset($values['value'])) {
          $values['value'] = $value;
        }
        else {
          if (!is_array($values['value'])) {
            $values['value'] = array(
              $values['value'],
            );
          }
          $values['value'][] = $value;
        }
      }
      unset($values[$k]);
    }
    return $values;
  }

  /**
   * Constant ::= integer | string | float | boolean
   *
   * @throws AnnotationException
   * @return mixed
   */
  private function Constant() {
    $identifier = $this
      ->Identifier();
    if (!defined($identifier) && false !== strpos($identifier, '::') && '\\' !== $identifier[0]) {
      list($className, $const) = explode('::', $identifier);
      $alias = false === ($pos = strpos($className, '\\')) ? $className : substr($className, 0, $pos);
      $found = false;
      switch (true) {
        case !empty($this->namespaces):
          foreach ($this->namespaces as $ns) {
            if (class_exists($ns . '\\' . $className) || interface_exists($ns . '\\' . $className)) {
              $className = $ns . '\\' . $className;
              $found = true;
              break;
            }
          }
          break;
        case isset($this->imports[$loweredAlias = strtolower($alias)]):
          $found = true;
          if (false !== $pos) {
            $className = $this->imports[$loweredAlias] . substr($className, $pos);
          }
          else {
            $className = $this->imports[$loweredAlias];
          }
          break;
        default:
          if (isset($this->imports['__NAMESPACE__'])) {
            $ns = $this->imports['__NAMESPACE__'];
            if (class_exists($ns . '\\' . $className) || interface_exists($ns . '\\' . $className)) {
              $className = $ns . '\\' . $className;
              $found = true;
            }
          }
          break;
      }
      if ($found) {
        $identifier = $className . '::' . $const;
      }
    }
    if (!defined($identifier)) {
      throw AnnotationException::semanticalErrorConstants($identifier, $this->context);
    }
    return constant($identifier);
  }

  /**
   * Identifier ::= string
   *
   * @return string
   */
  private function Identifier() {

    // check if we have an annotation
    if ($this->lexer
      ->isNextTokenAny(self::$classIdentifiers)) {
      $this->lexer
        ->moveNext();
      $className = $this->lexer->token['value'];
    }
    else {
      $this
        ->syntaxError('namespace separator or identifier');
    }
    while ($this->lexer->lookahead['position'] === $this->lexer->token['position'] + strlen($this->lexer->token['value']) && $this->lexer
      ->isNextToken(DocLexer::T_NAMESPACE_SEPARATOR)) {
      $this
        ->match(DocLexer::T_NAMESPACE_SEPARATOR);
      $this
        ->matchAny(self::$classIdentifiers);
      $className .= '\\' . $this->lexer->token['value'];
    }
    return $className;
  }

  /**
   * Value ::= PlainValue | FieldAssignment
   *
   * @return mixed
   */
  private function Value() {
    $peek = $this->lexer
      ->glimpse();
    if (DocLexer::T_EQUALS === $peek['type']) {
      return $this
        ->FieldAssignment();
    }
    return $this
      ->PlainValue();
  }

  /**
   * PlainValue ::= integer | string | float | boolean | Array | Annotation
   *
   * @return mixed
   */
  private function PlainValue() {
    if ($this->lexer
      ->isNextToken(DocLexer::T_OPEN_CURLY_BRACES)) {
      return $this
        ->Arrayx();
    }
    if ($this->lexer
      ->isNextToken(DocLexer::T_AT)) {
      return $this
        ->Annotation();
    }
    if ($this->lexer
      ->isNextToken(DocLexer::T_IDENTIFIER)) {
      return $this
        ->Constant();
    }
    switch ($this->lexer->lookahead['type']) {
      case DocLexer::T_STRING:
        $this
          ->match(DocLexer::T_STRING);
        return $this->lexer->token['value'];
      case DocLexer::T_INTEGER:
        $this
          ->match(DocLexer::T_INTEGER);
        return (int) $this->lexer->token['value'];
      case DocLexer::T_FLOAT:
        $this
          ->match(DocLexer::T_FLOAT);
        return (double) $this->lexer->token['value'];
      case DocLexer::T_TRUE:
        $this
          ->match(DocLexer::T_TRUE);
        return true;
      case DocLexer::T_FALSE:
        $this
          ->match(DocLexer::T_FALSE);
        return false;
      case DocLexer::T_NULL:
        $this
          ->match(DocLexer::T_NULL);
        return null;
      default:
        $this
          ->syntaxError('PlainValue');
    }
  }

  /**
   * FieldAssignment ::= FieldName "=" PlainValue
   * FieldName ::= identifier
   *
   * @return array
   */
  private function FieldAssignment() {
    $this
      ->match(DocLexer::T_IDENTIFIER);
    $fieldName = $this->lexer->token['value'];
    $this
      ->match(DocLexer::T_EQUALS);
    $item = new \stdClass();
    $item->name = $fieldName;
    $item->value = $this
      ->PlainValue();
    return $item;
  }

  /**
   * Array ::= "{" ArrayEntry {"," ArrayEntry}* [","] "}"
   *
   * @return array
   */
  private function Arrayx() {
    $array = $values = array();
    $this
      ->match(DocLexer::T_OPEN_CURLY_BRACES);
    $values[] = $this
      ->ArrayEntry();
    while ($this->lexer
      ->isNextToken(DocLexer::T_COMMA)) {
      $this
        ->match(DocLexer::T_COMMA);

      // optional trailing comma
      if ($this->lexer
        ->isNextToken(DocLexer::T_CLOSE_CURLY_BRACES)) {
        break;
      }
      $values[] = $this
        ->ArrayEntry();
    }
    $this
      ->match(DocLexer::T_CLOSE_CURLY_BRACES);
    foreach ($values as $value) {
      list($key, $val) = $value;
      if ($key !== null) {
        $array[$key] = $val;
      }
      else {
        $array[] = $val;
      }
    }
    return $array;
  }

  /**
   * ArrayEntry ::= Value | KeyValuePair
   * KeyValuePair ::= Key ("=" | ":") PlainValue | Constant
   * Key ::= string | integer | Constant
   *
   * @return array
   */
  private function ArrayEntry() {
    $peek = $this->lexer
      ->glimpse();
    if (DocLexer::T_EQUALS === $peek['type'] || DocLexer::T_COLON === $peek['type']) {
      if ($this->lexer
        ->isNextToken(DocLexer::T_IDENTIFIER)) {
        $key = $this
          ->Constant();
      }
      else {
        $this
          ->matchAny(array(
          DocLexer::T_INTEGER,
          DocLexer::T_STRING,
        ));
        $key = $this->lexer->token['value'];
      }
      $this
        ->matchAny(array(
        DocLexer::T_EQUALS,
        DocLexer::T_COLON,
      ));
      return array(
        $key,
        $this
          ->PlainValue(),
      );
    }
    return array(
      null,
      $this
        ->Value(),
    );
  }

}