Class: Puppet::Pops::Types::PTypeAliasType

Inherits:
PAnyType show all
Defined in:
lib/puppet/pops/types/types.rb

Overview

Describes a named alias for another Type. The alias is created with a name and an unresolved type expression. The type expression may in turn contain other aliases (including the alias that contains it) which means that an alias might contain self recursion. Whether or not that is the case is computed and remembered when the alias is resolved since guarding against self recursive constructs is relatively expensive.

Defined Under Namespace

Classes: AssertOtherTypeAcceptor, AssertSelfRecursionStatusAcceptor

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from PAnyType

#==, #callable?, #callable_with?, #create, create, #generalize, new_function, #normalize, #roundtrip_with_string?, #simple_name, simple_name, #to_alias_expanded_s

Methods inherited from TypedModelObject

_pcore_type, create_ptype, register_ptypes

Methods included from PuppetObject

#_pcore_all_contents, #_pcore_contents, #_pcore_init_hash, #_pcore_type

Constructor Details

#initialize(name, type_expr, resolved_type = nil) ⇒ PTypeAliasType

Returns a new instance of PTypeAliasType.

Parameters:

  • name (String)

    The name of the type

  • type_expr (Model::PopsObject)

    The expression that describes the aliased type

  • resolved_type (PAnyType) (defaults to: nil)

    the resolve type (only used for the DEFAULT initialization)


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# File 'lib/puppet/pops/types/types.rb', line 3370

def initialize(name, type_expr, resolved_type = nil)
  @name = name
  @type_expr = type_expr
  @resolved_type = resolved_type
  @self_recursion = false
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *arguments, &block) ⇒ Object

Delegates to resolved type


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# File 'lib/puppet/pops/types/types.rb', line 3539

def method_missing(name, *arguments, &block)
  super if @resolved_type.equal?(PTypeReferenceType::DEFAULT)
  resolved_type.send(name, *arguments, &block)
end

Instance Attribute Details

#loaderObject (readonly)


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# File 'lib/puppet/pops/types/types.rb', line 3365

def loader
  @loader
end

#nameObject (readonly)


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# File 'lib/puppet/pops/types/types.rb', line 3365

def name
  @name
end

Class Method Details

.register_ptype(loader, ir) ⇒ Object


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# File 'lib/puppet/pops/types/types.rb', line 3354

def self.register_ptype(loader, ir)
  create_ptype(loader, ir, 'AnyType',
     'name' => PStringType::NON_EMPTY,
     'type_expr' => PAnyType::DEFAULT,
     'resolved_type' => {
       KEY_TYPE => POptionalType.new(PTypeType::DEFAULT),
       KEY_VALUE => nil
     }
  )
end

Instance Method Details

#accept(visitor, guard) ⇒ Object


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# File 'lib/puppet/pops/types/types.rb', line 3514

def accept(visitor, guard)
  guarded_recursion(guard, nil) do |g|
    super(visitor, g)
    @resolved_type.accept(visitor, g) unless @resolved_type.nil?
  end
end

#assignable?(o, guard = nil) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3377

def assignable?(o, guard = nil)
  if @self_recursion
    guard ||= RecursionGuard.new
    guard.with_this(self) { |state| state == RecursionGuard::SELF_RECURSION_IN_BOTH ? true : super(o, guard) }
  else
    super(o, guard)
  end
end

#callable_args?(callable, guard) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3396

def callable_args?(callable, guard)
  guarded_recursion(guard, false) { |g| resolved_type.callable_args?(callable, g) }
end

#check_self_recursion(originator) ⇒ Object


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# File 'lib/puppet/pops/types/types.rb', line 3400

def check_self_recursion(originator)
  resolved_type.check_self_recursion(originator) unless originator.equal?(self)
end

#eql?(o) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3510

def eql?(o)
  super && o.name == @name
end

#hashObject


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# File 'lib/puppet/pops/types/types.rb', line 3420

def hash
  @name.hash
end

#instance?(o, guard = nil) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3408

def instance?(o, guard = nil)
  really_instance?(o, guard) == 1
end

#iterable?(guard = nil) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3412

def iterable?(guard = nil)
  guarded_recursion(guard, false) { |g| resolved_type.iterable?(g) }
end

#iterable_type(guard = nil) ⇒ Object


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# File 'lib/puppet/pops/types/types.rb', line 3416

def iterable_type(guard = nil)
  guarded_recursion(guard, nil) { |g| resolved_type.iterable_type(g) }
end

#kind_of_callable?(optional = true, guard = nil) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3404

def kind_of_callable?(optional=true, guard = nil)
  guarded_recursion(guard, false) { |g| resolved_type.kind_of_callable?(optional, g) }
end

#really_instance?(o, guard = nil) ⇒ Boolean

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3545

def really_instance?(o, guard = nil)
  if @self_recursion
    guard ||= RecursionGuard.new
    guard.with_that(o) do
      guard.with_this(self) { |state| state == RecursionGuard::SELF_RECURSION_IN_BOTH ? 0 : resolved_type.really_instance?(o, guard) }
    end
  else
    resolved_type.really_instance?(o, guard)
  end
end

#resolve(loader) ⇒ PTypeAliasType

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Called from the TypeParser once it has found a type using the Loader. The TypeParser will interpret the contained expression and the resolved type is remembered. This method also checks and remembers if the resolve type contains self recursion.

Parameters:

  • type_parser (TypeParser)

    type parser that will interpret the type expression

  • loader (Loader::Loader)

    loader to use when loading type aliases

Returns:


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# File 'lib/puppet/pops/types/types.rb', line 3470

def resolve(loader)
  @loader = loader
  if @resolved_type.nil?
    # resolved to PTypeReferenceType::DEFAULT during resolve to avoid endless recursion
    @resolved_type = PTypeReferenceType::DEFAULT
    @self_recursion = true # assumed while it being found out below
    begin
      if @type_expr.is_a?(PTypeReferenceType)
        @resolved_type = @type_expr.resolve(loader)
      else
        @resolved_type = TypeParser.singleton.interpret(@type_expr, loader).normalize
      end

      # Find out if this type is recursive. A recursive type has performance implications
      # on several methods and this knowledge is used to avoid that for non-recursive
      # types.
      guard = RecursionGuard.new
      real_type_asserter = AssertOtherTypeAcceptor.new
      accept(real_type_asserter, guard)
      unless real_type_asserter.other_type_detected?
        raise ArgumentError, "Type alias '#{name}' cannot be resolved to a real type"
      end
      @self_recursion = guard.recursive_this?(self)
      # All aliases involved must re-check status since this alias is now resolved
      if @self_recursion
        accept(AssertSelfRecursionStatusAcceptor.new, RecursionGuard.new)
        when_self_recursion_detected
      end
    rescue
      @resolved_type = nil
      raise
    end
  else
    # An alias may appoint an Object type that isn't resolved yet. The default type
    # reference is used to prevent endless recursion and should not be resolved here.
    @resolved_type.resolve(loader) unless @resolved_type.equal?(PTypeReferenceType::DEFAULT)
  end
  self
end

#resolved_typePAnyType

Returns the resolved type. The type must have been resolved by a call prior to calls to this method or an error will be raised.

Returns:

  • (PAnyType)

    The resolved type of this alias.

Raises:

  • (Puppet::Error)

    unless the type has been resolved prior to calling this method


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# File 'lib/puppet/pops/types/types.rb', line 3391

def resolved_type
  raise Puppet::Error, "Reference to unresolved type #{@name}" unless @resolved_type
  @resolved_type
end

#respond_to_missing?(name, include_private) ⇒ Boolean

Delegates to resolved type

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3534

def respond_to_missing?(name, include_private)
  resolved_type.respond_to?(name, include_private)
end

#self_recursion?Boolean

Returns:

  • (Boolean)

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# File 'lib/puppet/pops/types/types.rb', line 3521

def self_recursion?
  @self_recursion
end

#set_self_recursion_statusObject


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# File 'lib/puppet/pops/types/types.rb', line 3453

def set_self_recursion_status
  return if @self_recursion || @resolved_type.is_a?(PTypeReferenceType)
  @self_recursion = true
  guard = RecursionGuard.new
  accept(NoopTypeAcceptor::INSTANCE, guard)
  @self_recursion = guard.recursive_this?(self)
  when_self_recursion_detected if @self_recursion # no difference
end

#to_sString

Returns the expanded string the form of the alias, e.g. <alias name> = <resolved type>

Returns:

  • (String)

    the expanded form of this alias


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# File 'lib/puppet/pops/types/types.rb', line 3529

def to_s
  TypeFormatter.singleton.alias_expanded_string(self)
end

#type_exprObject

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns `nil` to prevent serialization of the type_expr used when first initializing this instance.

Returns:

  • `nil` to prevent serialization of the type_expr used when first initializing this instance


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# File 'lib/puppet/pops/types/types.rb', line 3558

def type_expr
  nil
end