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, #generalize, new_function, #normalize, simple_name, #simple_name, #to_alias_expanded_s

Methods inherited from TypedModelObject

_ptype, create_ptype, register_ptypes

Methods included from PuppetObject

#_ptype

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)



3147
3148
3149
3150
3151
3152
 
# File 'lib/puppet/pops/types/types.rb', line 3147

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



3315
3316
3317
3318
 
# File 'lib/puppet/pops/types/types.rb', line 3315

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

Instance Attribute Details

#name ⇒ Object (readonly) 



3142
3143
3144
 
# File 'lib/puppet/pops/types/types.rb', line 3142

def name
  @name
end

Class Method Details

.register_ptype(loader, ir) ⇒ Object 



3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
 
# File 'lib/puppet/pops/types/types.rb', line 3131

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(PType::DEFAULT),
       KEY_VALUE => nil
     }
  )
end

Instance Method Details

#accept(visitor, guard) ⇒ Object 



3290
3291
3292
3293
3294
3295
 
# File 'lib/puppet/pops/types/types.rb', line 3290

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) 


3154
3155
3156
3157
3158
3159
3160
3161
 
# File 'lib/puppet/pops/types/types.rb', line 3154

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) 


3173
3174
3175
 
# File 'lib/puppet/pops/types/types.rb', line 3173

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

#check_self_recursion(originator) ⇒ Object 



3177
3178
3179
 
# File 'lib/puppet/pops/types/types.rb', line 3177

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

#eql?(o) ⇒ Boolean

Returns:

  • (Boolean) 


3286
3287
3288
 
# File 'lib/puppet/pops/types/types.rb', line 3286

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

#hash ⇒ Object 



3197
3198
3199
 
# File 'lib/puppet/pops/types/types.rb', line 3197

def hash
  @name.hash
end

#instance?(o, guard = nil) ⇒ Boolean

Returns:

  • (Boolean) 


3185
3186
3187
 
# File 'lib/puppet/pops/types/types.rb', line 3185

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

#iterable?(guard = nil) ⇒ Boolean

Returns:

  • (Boolean) 


3189
3190
3191
 
# File 'lib/puppet/pops/types/types.rb', line 3189

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

#iterable_type(guard = nil) ⇒ Object 



3193
3194
3195
 
# File 'lib/puppet/pops/types/types.rb', line 3193

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) 


3181
3182
3183
 
# File 'lib/puppet/pops/types/types.rb', line 3181

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) 


3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
 
# File 'lib/puppet/pops/types/types.rb', line 3321

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(type_parser, 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:



3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
 
# File 'lib/puppet/pops/types/types.rb', line 3247

def resolve(type_parser, 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(type_parser, loader)
      else
        @resolved_type = type_parser.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(type_parser, 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



3168
3169
3170
3171
 
# File 'lib/puppet/pops/types/types.rb', line 3168

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) 


3310
3311
3312
 
# File 'lib/puppet/pops/types/types.rb', line 3310

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

#self_recursion? ⇒ Boolean

Returns:

  • (Boolean) 


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

def self_recursion?
  @self_recursion
end

#set_self_recursion_status ⇒ Object 



3230
3231
3232
3233
3234
3235
3236
3237
 
# File 'lib/puppet/pops/types/types.rb', line 3230

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



3305
3306
3307
 
# File 'lib/puppet/pops/types/types.rb', line 3305

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



3334
3335
3336
 
# File 'lib/puppet/pops/types/types.rb', line 3334

def type_expr
  nil
end