This research presents a re-engineering workbench and architecture that allows for legacy system written in procedural languages to be migrated to new objectoriented platforms. This methodology allows for specific de...
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The objectoriented Functional Data Language (O²FDL) is an interactive strongly-typed database programming language that integrates the object-oriented and functional programming paradigms. It was designed for ad...
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The objectoriented Functional Data Language (O²FDL) is an interactive strongly-typed database programming language that integrates the object-oriented and functional programming paradigms. It was designed for advanced applications such as computer-aided design, statistical computing, and multimedia systems that require a powerful and uniform database programming language supporting the software engineering principles of these two paradigms. To this end, the O²FDL supports inheritance and encapsulation of object-oriented languages, and an equational notation and strong typing of functional programming. Strong typing is extended with type restrictions to constrain the instantiations of type variables in function interfaces, while inheritance is augmented with a monotonic subtype rule for function redefinition. To facilitate convenient and concise expressions for both database and general purpose computation, the O²FDL supports novel features including 1) functions of indefinite nesting levels that simplify nested list processing; 2) system-defined functions that provide a concise and convenient notation for filtering, aggregating, and combining objects; and 3) path expressions that allow a flexible graphical correspondence for database queries. We define these features informally through examples and formally through a two pad semantics. For the core of the O²FDL we provide a denominational semantics based on an extended A-calculus. For selected system-defined functions, we provide an operational semantics and demonstrate that a subset of the O²FDL is at least as expressive as the relational algebra. [ABSTRACT FROM AUTHOR]
A commonly held belief is that applications written in object-oriented languages are more modular than those written in procedural languages. This paper presents results from an experiment that examines this hypothesi...
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ISBN:
(纸本)0769517579
A commonly held belief is that applications written in object-oriented languages are more modular than those written in procedural languages. This paper presents results from an experiment that examines this hypothesis. Open source and industrial program modules written in the procedural languages of Fortran and C were compared with open source program modules written in the object-oriented languages of C+ + and Java. The metrics examined in this study were lines of code per module and number of parameters per module. The results of the investigation support the hypothesis. The modules of the object-oriented programs were found to be half the size of those of the procedural programs and the average number of parameters per module for the object-oriented programs was approximately half that of the procedural programs. Thus the object-oriented programs were twice as modular as the procedural programs. An unexpected result was that the C+ + programs were found to be no more modular than the C programs.
This poster will present the work of Oopsla 2000 workshop 13, on "Active Learning For object-oriented Design". Many people are introduced to OO concepts, hut only learn the words. This workshop will explore ...
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GROOP is an object-oriented toolkit for creating 3D computer graphics applications. It is designed for application developers who are not familiar with computer graphics, but are familiar with object-oriented programm...
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We see a trend toward extending object-oriented languages in the direction of databases, and, at the same time, toward extending database systems with object-oriented ideas. On the surface, these two activities seem t...
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In this paper, we describe a purely object-oriented framework of pattern recognition systems. Its aim is in dealing with knowledge representation issues in pattern recognition. In our approach, everything works in an ...
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ISBN:
(纸本)0897912845
In this paper, we describe a purely object-oriented framework of pattern recognition systems. Its aim is in dealing with knowledge representation issues in pattern recognition. In our approach, everything works in an entirely autonomous and decentralized manner, Even a search procedure for sample-concept matching is distributed onto every concept object itself by being implemented in what we introduced as the recursive agent-blackboard model. We developed an experimental prototype of character recognition systems in Smalltalk-80, which proved the ability of the object-oriented framework and the cooperative search procedure.
The central idea behind this paper is that the discipline governing the exchange of messages between objects should be specifiable by the programmer in the form of an explicit law of the system. We show how, starting ...
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By-name subtyping (or user-defined subtyping) and structural subtyping each have their own strengths and weaknesses. By-name subtyping allows programmers to explicitly express design intent, and, when types are associ...
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ISBN:
(纸本)9781595938657
By-name subtyping (or user-defined subtyping) and structural subtyping each have their own strengths and weaknesses. By-name subtyping allows programmers to explicitly express design intent, and, when types are associated with run time tags, enables run-time "type" tests and external/multimethod dispatch. On the other hand, structural subtyping is flexible and compositional, allowing unanticipated reuse. To date, nearly all object-oriented languages fully support only one subtyping paradigm or the other. I propose a language that combines the key aspects of by- name and structural subtyping in a unified framework. The goal is to provide the flexibility of structural subtyping while still allowing static typechecking of external methods. The work offers a clean foundation for the design of future languages that enjoy the benefits of both by-name and structural subtyping. I also propose a language extension to Java that combines by-name and structural subtyping, and includes parametric polymorphism. The practical utility of this language will be illustrated through case studies that show that code written in the new language is more flexible and easier to modify than the original code.
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