Parrot Virtual Machine/Built-In PMCs
Built-in PMCs
editParrot ships with a number of PMC data types built in. This means that these standard types are always available. This page is going to serve as a reference to these PMC types. We will not attempt to cover all the PMC types that are added specifically for other HLLs, libraries, or programs. (For information on using these PMC types, and on defining new PMC types, see the Parrot Virtual Machine/Polymorphic Containers (PMCs) chapter).
The entries in this list should (A) contain a link to the relevant PMC documentation, and (B) provide a brief overview of the PMC and it's methods.
AddrRegistry
editArray
editA simple array class, serves as the base class for other array PMCs. This type of PMC is rarely used directly. Instead, more versatile array PMC types, such as ResizablePMCArray are used. Array specifies an interface that all other Array classes must share. It also provides a number of defaults that other array-like PMCs may default to.
BigInt
editA PMC type for storing an arbitrarily large number, or a number with arbitrary precision. Not currently implemented.
Boolean
editA boolean True/False PMC.
Bound_NCI
editCapture
editClosure
editCompiler
editA Compiler PMC for a particular language. Can be used to convert an HLL into PIR and eventually into Parrot Bytecode.
Complex
editA PMC for Complex numbers.
Continuation
editA Continuation PMC allows Parrot to take a snapshot of the current state of the system to return to later.
Coroutine
editA sub-like PMC that implements a coroutine.
Default
editDeleg_PMC
editDelegate
editEnumerate
editEnv
editAllows access to the system's environment variables, as a hash.
Eval
editException
editAn Exception PMC holds information about system errors for recovery.
Exception_Handler
editA sub-like routine that catches and resolves exceptions
Exporter
editFile
editA read/write interface for files
FixedBooleanArray
editAn array of fixed size of Boolean values.
FixedFloatArray
editAn array of fixed size for FLOATVAL floating point numbers
FixedPMCArray
editAn array of fixed size for PMC values
FixedStringArray
editAn array of fixed size for STRING values
Float
editA floating point number PMC. Used similarly to a FLOATVAL, except has methods and vtable methods. FLOATVALs become Float PMCs when they are promoted to become a PMC.
Hash
editA hash, also known as a "dictionary" or an "associative array". Like an array but indexed with strings instead of integers
Integer
editA basic integer number PMC. Used similarly to an INTVAL, but with methods and vtable methods. INTVALS become Integer PMCs when they are promoted to become a PMC.
IntList
editA simple list, or array, of integers.
Iterator
editAn Iterator PMC provides a stateful counter that enables you to iterate over the items in one of the array classes, one at a time.
Key
editA value, typically a string, which is used to look up values in a hash.
LexInfo
editLexPad
editManagedStruct
editA low-level structure whose memory is allocated and automatically deallocated by Parrot. Extends UnManagedStruct, but adds automatic memory collection.
MultiArray
editMultiSub
editA collection of subroutines with the same name. In Multiple Method Dispatch (MMD) the parameters of the function called determine which subroutine from the collection to call.
Mutable
editNamespace
editImplements a Parrot namespace. Contains information about variables, subroutines, coroutines, and MultiSubs that are stored in that namespace.
NCI
editA native call function PMC. Stores interface information to a function which has been written in C.
Null
editA PMC with a NUL value
Object
editOrderedHash
editOS
editPair
editAn association of a Key PMC with a PMC value. Hashes are typically implemented as an array of Pair PMCs
ParrotClass
editParrotInterpreter
editAn interface to the interpreter structure.
ParrotIO
editA read/write interface to the console
ParrotLibrary
editA dynamically-loaded library object.
ParrotObject
editParrotRunningThread
editParrotThread
editA PMC that stores information about a thread
Pmethod_test
editPointer
editRandom
editRef
editResizableBooleanArray
editA resizable array to store Boolean values
ResizableFloatArray
editA resizable array to store floating point values.
ResizableIntegerArray
editA resizable array to store integer values
ResizablePMCArray
editA resizable array to store PMC values
ResizableStringArray
editA resizable array to store Strings
RetContinuation
editA return continuation. Like a regular Continuation PMC, but can only be used once. Can be promoted to a Continuation using the Clone vtable method.
Role
editAn abstract role, or interface, for a class. Specifies actions and properties of a class, but cannot be instantiated
SArray
editSharedRef
editSlice
editSMOP_Attribute
editSMOP_Class
editSTMLog
editSTMRef
editSTMVar
editString
editA PMC to contain a string value. Like a STRING value, but has methods and vtable methods. STRINGS become String PMCs when they are promoted to PMCs.
Sub
editA Parrot subroutine. Implements a basic subroutine (using the sub command in PIR), but also serves as a base class for more intricate sub-like classes
Super
editA parent PMC class, to support multiple inheritance.
Timer
editTQueue
editUndef
editAn undefined PMC with no usable type.
UnamangedStruct
editA low-level structure which the programmer must manage manually. Parrot does not automatically collect memory allocated for the struct.