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)



3251
3252
3253
3254
3255
3256
 
# File 'lib/puppet/pops/types/types.rb', line 3251

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



3420
3421
3422
3423
 
# File 'lib/puppet/pops/types/types.rb', line 3420

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

Instance Attribute Details

#loader ⇒ Object (readonly) 



3246
3247
3248
 
# File 'lib/puppet/pops/types/types.rb', line 3246

def loader
  @loader
end

#name ⇒ Object (readonly) 



3246
3247
3248
 
# File 'lib/puppet/pops/types/types.rb', line 3246

def name
  @name
end

Class Method Details

.register_ptype(loader, ir) ⇒ Object 



3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
 
# File 'lib/puppet/pops/types/types.rb', line 3235

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 



3395
3396
3397
3398
3399
3400
 
# File 'lib/puppet/pops/types/types.rb', line 3395

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) 


3258
3259
3260
3261
3262
3263
3264
3265
 
# File 'lib/puppet/pops/types/types.rb', line 3258

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) 


3277
3278
3279
 
# File 'lib/puppet/pops/types/types.rb', line 3277

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

#check_self_recursion(originator) ⇒ Object 



3281
3282
3283
 
# File 'lib/puppet/pops/types/types.rb', line 3281

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

#eql?(o) ⇒ Boolean

Returns:

  • (Boolean) 


3391
3392
3393
 
# File 'lib/puppet/pops/types/types.rb', line 3391

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

#hash ⇒ Object 



3301
3302
3303
 
# File 'lib/puppet/pops/types/types.rb', line 3301

def hash
  @name.hash
end

#instance?(o, guard = nil) ⇒ Boolean

Returns:

  • (Boolean) 


3289
3290
3291
 
# File 'lib/puppet/pops/types/types.rb', line 3289

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

#iterable?(guard = nil) ⇒ Boolean

Returns:

  • (Boolean) 


3293
3294
3295
 
# File 'lib/puppet/pops/types/types.rb', line 3293

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

#iterable_type(guard = nil) ⇒ Object 



3297
3298
3299
 
# File 'lib/puppet/pops/types/types.rb', line 3297

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) 


3285
3286
3287
 
# File 'lib/puppet/pops/types/types.rb', line 3285

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) 


3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
 
# File 'lib/puppet/pops/types/types.rb', line 3426

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:



3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
 
# File 'lib/puppet/pops/types/types.rb', line 3351

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_type ⇒ PAnyType

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



3272
3273
3274
3275
 
# File 'lib/puppet/pops/types/types.rb', line 3272

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) 


3415
3416
3417
 
# File 'lib/puppet/pops/types/types.rb', line 3415

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

#self_recursion? ⇒ Boolean

Returns:

  • (Boolean) 


3402
3403
3404
 
# File 'lib/puppet/pops/types/types.rb', line 3402

def self_recursion?
  @self_recursion
end

#set_self_recursion_status ⇒ Object 



3334
3335
3336
3337
3338
3339
3340
3341
 
# File 'lib/puppet/pops/types/types.rb', line 3334

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_s ⇒ String

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

Returns:

  • (String) —

    the expanded form of this alias



3410
3411
3412
 
# File 'lib/puppet/pops/types/types.rb', line 3410

def to_s
  TypeFormatter.singleton.alias_expanded_string(self)
end

#type_expr ⇒ Object

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



3439
3440
3441
 
# File 'lib/puppet/pops/types/types.rb', line 3439

def type_expr
  nil
end