Francis G. McCabe. Logic and Objects. Prentice Hall, 1992.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....value of an instance inherited property, but cannot override that property. Monotonic instance inheritance is supported by terminological languages [7, 5, 24, 21, 4] and by several deductive object oriented models, such as DOT [27, 26] and QUIXOTE [28, 29] In contrast, several systems, such as [6, 14, 20, 1, 13, 17], support non monotonic instance inheritance, where the value of an instance inherited property can be overridden over subclasses, or over particular instances. In this section, we briefly compare our approach to instance inheritance to those mentioned above. In our comparison, we use the example ....

....car and Sports car may indicate erroneous schema declarations (see Appendix B) 8. 3 Shared value properties and default properties In the literature, inheritance from a class to its instances has been considered in connection with shared value properties [15, 23] and default properties [6, 14, 20, 1, 13, 17] . A sharedvalue property is a property with the same value for all instances of a class. Such a property is associated with the class, and not with particular instances of the class. Then, particular instances inherit the property from the class. For example, has material is a shared value ....

F.G. McCabe, Logic and Objects, Prentice Hall (1992).

....sharing and hiding, etc. which are all important means to manage the complexity of a particular domain. The desire to have in Prolog means for dividing a program into smaller relatively separated and independent units with transparent minimal interfaces has been responded by several authors [21, 11, 18, 16, 15, 19, 26]. Problems are encounteredwhen trying to combine logic databases (modules) Several approaches have been tried e.g. inheritance [19] context switching [16] introducing implication into goals [11] different definitions of visibility of atoms [18] using abstraction in separating the logic ....

.... by several authors [21, 11, 18, 16, 15, 19, 26] Problems are encounteredwhen trying to combine logic databases (modules) Several approaches have been tried e.g. inheritance [19] context switching [16] introducing implication into goals [11] different definitions of visibility of atoms [18], using abstraction in separating the logic database from the concrete implementation by specifying required resources and produced results [21] The mutual communication among logic databases has not been solved satisfactorily so far. No generally applicable strategy has been proposed that could ....

F.G. McCabe. Logic and Objects. Prentice Hall, 1992.

....of axioms, atomic inheritance refers to their atomic consequences. Although both aspects of content inheritance are useful to knowledge representation, existing combinations of logic and objects, except [21] address either complete inheritance (e.g. 7, 15, 18] or atomic inheritance (e.g. [20]) but not both as SILO does. Apart from various inheritance aspects, there are also a number of knowledge specialisation types (or specialisations) required for knowledge representation. The more specialisations an inheritance mechanism is able to support the more flexible a system is in ....

....in SILO through consequence retraction and exception by negation. Moreover, because SILO uses typed terms, a group of atomic forms can be represented via a single axiom and also a group of solutions can be invalidated via a single axiom. Finally, multiple inheritance is not treated in [21] In [20], a graph of objects is constructed using only two types of inheritance: full inheritance and overriding inheritance. Multiple inheritance is supported. However, it only deals with atomic inheritance. Although, default reasoning can be achieved, exception of axioms cannot be implemented. 36 The ....

F.G. McCabe, Logic and Objects (Prentice Hall, 1992).

....class message is a class object, whereas of an instance message one or more specific instance objects. An instance message corresponds to the traditional extensional message used in class based languages. A class message is a generalisation of the intentional or anonymous [18] or broadcast [19] message. When the receiver is the object object, then a class message is identical to an intentional message. For example, plays x george) in ( plays x george) plays x john) stored in john is an instance message, whereas (son y x:woman) in ( son y self) son y x:woman) wife ....

....make G c = G c # C c ; goto step 13. 18) Set Q = FAIL and make G = G # C . 19) If G c is not empty, set C c = first(G c ) G c = rest(G c ) and I c = I C . 20) Goto step 5. The class based proof process is a generalisation of what is called object search (e.g. in [19]) A class based proof process eventually ends up to one or more instance based processes. While an instance based process goes bottom up via inheritance links relations, a class based process goes top down via specialisation links relations, before it results in a number of instance based ....

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F. G. McCabe, Logic and Objects, :Prentice Hall (1992).

....logic programming has attracted great interests. The objective is to gain the best of both approaches. Various methods of incorporating object oriented programming into Prolog have been discussed [5, 13, 14] Also, a number of novel languages have been proposed such as OOLP [3] C Logic [2] L O [11], Prolog [12] COMPLEX [4] LIFE [1] and some of them have been implemented. However, none of them support all important object oriented features. In this paper, we describe Pluto, an object oriented logic programming language that supports nearly all object oriented features in a logic ....

F. G. McCabe. Logic and Objects. Prentice Hall., 1992.

....of deductive objects. More precisely, the characterization of objects as logic theories, coming from object oriented extensions of logic programming, does not account for any notion of state. McCabe suggests that the change of state for an instance can be simulated by creating new instances [McC88] Other proposals simulate state changes by using assert and retract but this approach lacks any logical foundation. In [CW88] intensional variables are introduced to keep trace of state changes without side effects. In other proposals, multi headed clauses are used for similar purposes. However, ....

....not consider the behavioral component of objects, that is, methods. We think that this is an important issue because it overcomes the dichotomy between data and operations of the relational model. Few proposals moreover, deal with behavioral inheritance and overriding. In addition to [ALUW93,LO91,McC88] these topics have been addressed in [BJ95,DT95,JL95] All these proposals extend F logic [KL90] or F logic variations) with behavioral inheritance. In F logic, indeed, only structural inheritance is directly captured. For behavioral inheritance, the non monotonic aspects introduced by the ....

F.G. McCabe. Logic and Objects. PhD thesis, University of London, November 1988.

....used for this purpose in other object oriented systems. An objectidentifier can be a compound term. The arguments of the term are parameters that are visible in the object body. Here we show one example. Other examples and techniques that use this facility has been investigated extensively in [McCabe 92] Chapter 35: SICStus Objects 409 The following is an object sort that sorts lists of di#erent types. sort has a parameter that defines the type of the elements of the list. Notice that Type is visible to all methods in the body of sort, and is used in the method partition 4. In the query, we ....

F. McCabe, Logic and Objects, Prentice Hall, 1992.

....base can be partitioned to maintain data hiding. Fril knowledge base Object B property b knowledge base partitions low level, strict, Object A Object C property a property c Figure 1: Strict knowledge base partitioning Implement a virtual knowledge base partitioning similar to McCabe s[8]. In this case every property in every class must have a unique identifier and all properties exist in the same global knowledge base. The compiler will only compile calls to other objects that are permissible. Unfortunately, for this to be robust where meta programming is used, a high degree of ....

....step decomposes a complete class definition into its components (super classes, constants, attributes, and methods) and then generates a Fril predicate for each of the components. Each component is uniquely identified through a label translation process similar to that proposed by McCabe[8]. 4.2.2 Object labelling When an object contains other objects it is referred to as a container object. In these cases the link between the container object and the contained object must be preserved after compilation. Within a method any contained objects are referred to using a chained dot . ....

F.G.McCabe, Logic and Objects, 1992, Prentice Hall

....would not allow such a message to pass. All features of the underlying logic programming language such as meta programming are retained. Figure 1 shows how the knowledge base can be partitioned to maintain data hiding. Implement a virtual knowledge base partitioning similar to McCabe s[8]. In this case every property in every class must have a unique identi er and all properties exist in the same global knowledge base. The compiler will only compile calls to other objects that are permissible. Unfortunately, for this to be robust where meta programming is used, a high degree of ....

....translation step decomposes a complete class definition into its components (super classes, constants, attributes, and methods) and then generates a Fril predicate for each of the components. Each component is uniquely identi ed through a label translation process similar to that proposed by McCabe[8]. 4.2.2 Object labelling When an object contains other objects it is referred to as a container object. In these cases the link between the container object and the contained object must be preserved after compilation. Within a method any contained objects are referred to using a chained dot . ....

F.G.McCabe, Logic and Objects, 1992, Prentice Hall

....to be solved by a single methodology or technique, combinations of different disciplines have been the quest and focus of significant research effort. In particular, logic programming and object oriented programming have been combined, resulting in objectoriented logic programming languages (e.g. [30], 13] 26] At this juncture, on the one hand, logic programming provides a declarative way for problem specification, well founded semantics for formal reasoning, and non deterministic mechanism for solution searching. On the other hand, object oriented programming provides class and object ....

....[36] and [14] did not discuss the problem, while [19] and [33] considered only multiple inheritance of attributes. In [12] the solution in the conventional object oriented model was adopted, whereby the selected method was the one of the first super class found in some ordering. As argued in [30], such an ordering based selection was not sufficient. Meanwhile, that selection problem disappears from the viewpoint of logic programming. Indeed, in the logicbased object oriented model, a property can be represented by a clause, where an attribute is represented by a fact and a method by a ....

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McCabe, F.G. 1992. Logic and Objects. Prentice Hall.

....with formulas weighted by probabilitybased degrees or possibility based degrees, respectively. This paper applies the proposed probability based scheme to the implementation of Fril by writing a translator to convert a Fril source program to a Fril target program, following the approach of [12]. Section 2 presents an overview of a Fril system and the translation process. Section 3 introduces Fril syntax and Section 4 discusses related semantic issues. Then Section 5 presents our translation strategy and illustrates translated codes. Finally, Section 6 presents concluding remarks of ....

....a class B based on a fuzzy matching of their descriptions, then B usually also has some inclusion degree to A. Second, naturally, a concept is usually classified into sub concepts that are totally subsumed by it, though the sub concepts can overlap each other. 2. 2 Translation Process As shown in [12], object oriented logic programs can be translated into normal logic programs, such as Prolog ones, to be executed almost as efficiently as the original programs would be. We follow this approach in the implementation of Fril by writing a translator, using Fril itself, to convert Fril programs ....

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McCabe, F.G. 1992. Logic and Objects. Prentice Hall.

.... and generalization play an extremely important role in the design of models and systems in software development (Switzer 1993) Whilst a hierarchy provides the ideal structure for modelling a domain, generalisation and specialisation provide the toolset for organising the knowledge within (McCabe 1992). Abstractions, representing classes from the domain, are defined into layers. The lower layers, or specialisations, are more specific; the higher layers, or generalisations, are less specific. The higher the level of abstraction, the greater the number of classes that can share its ....

....(extension) are reversed (Khoshafian and Abnous 1990) see figure 4.1) The term specialisation is widely used in the literature and there are several interpretations which conflict with the definition given above. Some writers, in fact, simply equate the terms inheritance and specialisation (McCabe 1992; Eckert 1994) Consequently, on occasion one may discover specialisation being used to refer to an inheritance relationship where superclass characteristics have been excluded. In the literature one also regularly sees specialisation equated with the is a relation 33 Figure 4.1: Inclusion ....

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McCabe, F. G. (1992). Logic and Objects. Prentice Hall.

....Modular Logic Programming Delta 33 we proposed a logical explanation of modularity in terms of the basic semantics of logic programming, thus achieving a module calculus which is more geared to the distinguishing features of logic programming. Similar considerations apply to the proposal of McCabe [McCabe 1988], which introduces an object oriented logic language by translating it back to Prolog. ....

McCabe, F. 1988. Logic and Objects. Ph. D. thesis, Imperial College of Science and Technology.

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Francis G. McCabe. Logic and Objects. Prentice Hall, 1992.

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McCabe, F.G. 1988.Logic and Objects, PhD Thesis, Dept. of Computing, Imperial College, London.

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F.G. McCabe, Logic and Objects, Prentice Hall, 1992.

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F. G. McCabe. Logic And Objects. Technical Report, Department of Computing, Imperial College, 1988.

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F. G. McCabe. Logic and Objects. Prentice Hall, 1992.

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F. G. McCabe. Logic and Objects. Prentice Hall, 1992.

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F.G. McCabe, Logic and Objects, Prentice Hall, (1992).

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McCabe, F.G. (1992). Logic and Objects. Prentice Hall.

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F. McCabe, [1992], "Logic and Objects", Prentice Hall International (UK) Ltd

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F.G. Mccabe. Logic and Objects, Prentice Hall, Englewood Cliffs, N J, 1992.

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McCabe, F.G. 1988. Logic and Objects, PhD Thesis, Dept. of Computing, Imperial College, London.

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McCabe,F.G. Logic and Objects. Prentice Hall, 1992.

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