3. Aspects

3.1 High-Level

3.1.1 Introduction

The High-Level aspect of a TUNES system includes all objects required to define any ABSTRACTION within the system.

3.1.2 Types

Object

All elements of the system. Within this document, any unqualified use of this term means any element of a TUNES system. Objects may be manifest or implicit in a particular context, but there will at all times be some mechanism(s) available to make any object manifest within a context.

Attribution

An OBJECT relating a source object to an attribute object via a key object. An attribution may be static or dynamically-resolved, and (side-)effecting or not.

Meta-Object

The term for an OBJECT which deals with some part of the essential characteristics of another. An object can be a meta-object of another object independently of whether or not it provides some function of the implementation of that target object. There are various types of meta-objects. Each meta-object type that deals with a universal kind of aspect of objects may be a meta-object of any object in the system without restriction.

Configuration

An OBJECT representing some requirements on the relationships between some collection of objects.

Context

Any OBJECT encapsulating the implicit meaning of another object. The nature of a context object determines how an object is expressed within that context. The expression of an object within a context is the object's creation, so there is some definite orientation of the object to that context.
Unlike the term used within human linguistics, there is no natural lack of access to the original context, so a TUNES system only engages in contextual forensics for external systems or internal, unpredictable systems.

Type

Any OBJECT representing a class of properties that another OBJECT or CONFIGURATION of objects satisfies. All objects have types; all objects may have multiple types. The type of an object is in one way self-defining: each object satisfies properties that distinguish it from other objects, and this is precisely what distinguishes objects.

Type System

The term for a collection of types along with operations on those types and some form of relations between them.

Effect

An OBJECT representing a change in the system. These can be provided at various abstraction levels, and the changes themselves may have varying semantics. It is nevertheless the required case that for every effect there must be an expression of it as a function on the system.^3.1

Expression

An OBJECT representing another in some linguistic CONTEXT.

Side-Effect

The term for an EFFECT not encoded expressly in some EXPRESSION.

3.1.3 Operations

Apply

Couples an ABSTRACTION expression with an input expression.^3.2

Abstract (or lambda)

Creates a function by specifying a REWRITE with an input CONFIGURATION and some body expressions.

Instantiate (or epsilon)

 

Replace

 

3.2 Meta-Linguistic

3.2.1 Introduction

The Meta-Linguistic aspect of a TUNES system includes all objects which deal with the expression of languages and relation and translation issues between them.

3.2.2 Types

Expression

An OBJECT representing another in some linguistic CONTEXT.

Specification

An EXPRESSION describing a CONFIGURATION.

3.2.3 Operations

Parse

Transform a stream of (character) objects into an OBJECT structure

Expand

Code-transformation techniques that are transparent to the semantics of the program specification itself.

Search

Control of evaluation order within the limits of the evaluation-order requirements of the semantics of the CONTEXT.

Dispatch

Taking each APPLICATION expression, consisting of a function designator and its arguments, and determining according to the environment and its function-definition semantics, and identifying the right function-definition or combinations thereof to APPLY.

Rewrite

Applying EFFECTs specified by the program to the system.

Respond

Communicating the effects of some REWRITE to the calling context.

Translate

 

3.3 Interface

3.3.1 Introduction

The Interface aspect of the TUNES system includes all objects whose purpose relates to the display of information for a user and meaningful interaction with users.

3.3.2 Types

User

An OBJECT representing a particular human user or agent thereof that interacts through a TERMINAL device. User objects have an associated environment which carries the vocabulary and preferences specific to that user.

Terminal

An interaction component of the system, consisting of at least one input and one output device.

Gesture

A unit OBJECT of input or output interaction. The TERMINAL device's characteristics determine the possible granularity of these objects.

Command

An OBJECT representing a single event or combination of events which have been given some meaning by their presence within some interaction CONTEXT.

Activity

An OBJECT representing a user's model of some sequence of events directed towards a perceived specified objective.

Medium

An OBJECT representing a particular interaction device, with its characteristics, behavior, and state. All objects of this TYPE are subject to a generic protocol which allows for abstraction within the limits of the device capabilities.

Display

An OBJECT representing an abstract rendering device.^3.3

Color

An OBJECT representing a visual color, a kind of DESIGN.

Style

An OBJECT representing a set of options and settings for rendering something on a DISPLAY.

Region

An OBJECT representing a geometric space of some dimension.

Design

An OBJECT representing any graphical pattern. Designs may be composed with each other into final designs.

Presentation

An OBJECT which contains presentation aspects of the rendering of some object. Presentation objects may have formatting options and their own user-centric type notion separate from the type of the presented object.

Morph

An object whose context is a display. Objects of this type are those which offer the user some form of direct manipulation and do not inherently concern the presentation of some other object.

World

An object representing some site on a DISPLAY.

Portal

An object representing some channel between sites or a bus among sites on a display.

3.3.3 Operations

Draw

Rendering a display OBJECT onto a DISPLAY with some particular STYLE.

Print

Rendering an OBJECT onto a DISPLAY in a form suitable for direct input to some reader.

Read

Creating an OBJECT from some input description.

Present

 

Request

 

Accept

 

3.4 Migration

3.4.1 Introduction

The Migration aspect of a TUNES system includes all objects which describe the identity and relate to mechanisms for moving or duplicating objects between any kind of contexts.

3.4.2 Types

Module

A CONFIGURATION of OBJECTs with formal requirements for comprehension and formal provisions.

Site

A source or target of communication.

Protocol

A medium of communication. Precisely, a language/encoding.

Stream

A possibly endless sequence of objects, sent between sites.

Packet

A single element of a stream.

Memory Region

A subset of a storage device with a particular management type for its memory.

Space

^3.4A sharable OBJECT which provides a means of accessing publications.

Reference

An encoding of a remote OBJECT; generally, a program to retrieve an object for use.

Persistent Store

 

Version

 

3.4.3 Operations

Reify

Takes some SPECIFICATION of the target CONTEXT, and removes an OBJECT from a source CONTEXT based on the required elements. It slices the OBJECT from the CONTEXT, and represents the relevant parts to send to the target CONTEXT.

Communicate

Renders the MODULE in some medium that both the source and target CONTEXTs advertise that they support, and actually transports the MODULE's contents as necessary.

Absorb

Takes a description of some MODULE to receive, and evaluates as necessary to install the objects in the target CONTEXT.

Publish

Registers some MODULE within a SPACE, with a TYPE and a VERSION known to some shared server SITE which can mediate the exchange. SPACEs themselves can notably be published.

3.5 Low-Level

3.5.1 Introduction

The Low-Level aspect of a TUNES system involves all objects whose sole role involves the implementation of other objects in the system.

3.5.2 Types

Bit

A single discrete unit of memory with two possible states.

Word

A vector of BITs defined as a unit of memory for some (possibly abstract) machine.

Memory

A quantity of information managed and storable by some device.

Processor

An operational machine that processes information stored in MEMORY.

Channel

A structure through which information is passed between two SITEs or OBJECTs, which can have state and modes. Channels can be concrete or abstract, and abstract channels can be emulated by other channels through agreed protocols.

Bus

A shared communications medium, having many publishers and subscribers to information. A bus can often be considered in terms of many cooperating CHANNELs.

Thread

An OBJECT representing a unit of execution, possibly with an associated voucher for PROCESSOR resources.

Encoding

An OBJECT representing a particular TYPE of low-level representation for some other type of OBJECT.

3.5.3 Operations

Bootload

 

Call

 

Allocate

 

De-allocate

 

Encode

 

Decode