scholarly journals Object-Oriented Type Inference

1991 ◽  
Vol 20 (345) ◽  
Author(s):  
Jens Palsberg ◽  
Michael I. Schwartzbach

We present a new approach to inferring types in untyped object-oriented programs with inheritance, assignments, and late binding. It guarantees that all messages are understood, annotates the program with type information, allows polymorphic methods, and can be used as the basis of an optimizing compiler. Types are finite sets of classes and subtyping is set inclusion. Using a trace graph, our algorithm constructs a set of conditional type constraints and computes the least solution by least fixed-point derivation.

Author(s):  
Tianxing Wu ◽  
Guilin Qi ◽  
Bin Luo ◽  
Lei Zhang ◽  
Haofen Wang

Extracting knowledge from Wikipedia has attracted much attention in recent ten years. One of the most valuable kinds of knowledge is type information, which refers to the axioms stating that an instance is of a certain type. Current approaches for inferring the types of instances from Wikipedia mainly rely on some language-specific rules. Since these rules cannot catch the semantic associations between instances and classes (i.e. candidate types), it may lead to mistakes and omissions in the process of type inference. The authors propose a new approach leveraging attributes to perform language-independent type inference of the instances from Wikipedia. The proposed approach is applied to the whole English and Chinese Wikipedia, which results in the first version of MulType (Multilingual Type Information), a knowledge base describing the types of instances from multilingual Wikipedia. Experimental results show that not only the proposed approach outperforms the state-of-the-art comparison methods, but also MulType contains lots of new and high-quality type information.


2022 ◽  
pp. 580-606
Author(s):  
Tianxing Wu ◽  
Guilin Qi ◽  
Bin Luo ◽  
Lei Zhang ◽  
Haofen Wang

Extracting knowledge from Wikipedia has attracted much attention in recent ten years. One of the most valuable kinds of knowledge is type information, which refers to the axioms stating that an instance is of a certain type. Current approaches for inferring the types of instances from Wikipedia mainly rely on some language-specific rules. Since these rules cannot catch the semantic associations between instances and classes (i.e. candidate types), it may lead to mistakes and omissions in the process of type inference. The authors propose a new approach leveraging attributes to perform language-independent type inference of the instances from Wikipedia. The proposed approach is applied to the whole English and Chinese Wikipedia, which results in the first version of MulType (Multilingual Type Information), a knowledge base describing the types of instances from multilingual Wikipedia. Experimental results show that not only the proposed approach outperforms the state-of-the-art comparison methods, but also MulType contains lots of new and high-quality type information.


1992 ◽  
Vol 21 (385) ◽  
Author(s):  
Nicholas Oxhøj ◽  
Jens Palsberg ◽  
Michael I. Schwartzbach

We present the implementation of a type inference algorithm for untyped object-oriented programs with inheritance, assignments, and late binding.The algorithm significantly improves our previous one, presented at OOPSLA'91, since it can handle collection classes, such as {\bf List}, in a useful way. Also, the complexity has been dramatically improved, from exponential time to low polynomial time. The implementation uses the techniques of incremental graph construction and constraint template instantiation to avoid representing intermediate results, doing superfluous work, and recomputing type information. Experiments indicate that the implementation type checks as much as 100 lines pr. second. This results in a mature product, on which a number of tools can be based, for example a safety tool, an image compression tool, a code optimization tool, and an annotation tool. This may make type inference for object-oriented languages practical.


Symmetry ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 512 ◽  
Author(s):  
Erdal Karapınar ◽  
Panda Kumari ◽  
Durdana Lateef

It is very well known that real-life applications of fixed point theory are restricted with the transformation of the problem in the form of f ( x ) = x . (1) The Knaster–Tarski fixed point theorem underlies various approaches of checking the correctness of programs. (2) The Brouwer fixed point theorem is used to prove the existence of Nash equilibria in games. (3) Dlala et al. proposed a solution for magnetic field problems via the fixed point approach.


1991 ◽  
Vol 20 (362) ◽  
Author(s):  
Jens Palsberg ◽  
Michael I. Schwartzbach

<p>This paper summarizes three discussions conducted at the ECOOP'91 W5 Workshop on ''Types, Inheritance, and Assignments'' Tuesday July 16, 1991 in Geneva, Switzerland, organized by the authors.</p><p> </p><p>The three discussions were entitled ''Classes versus Types'', ''Static versus Dynamic Typing'', and ''Type Inference''. All these topics were assumed to be volatile and controversial; indeed, a broad range of diverging opinions were represented. However, much superficial disagreement seemed to be rooted in confusions about terminology. When such issues were resolved, there appeared a consensus about basic definitions and the - often incompatible - choices that one is at liberty to make. This clarification, which we hope to have described below, was the most important achievement of the workshop.</p>


Author(s):  
JAE HUN CHOI ◽  
JAE DONG YANG ◽  
DONG GILL LEE

In this paper, we propose a new approach for managing domain specific thesauri, where object-oriented paradigm is applied to thesaurus construction and query-based browsing. The approach provides an object-oriented mechanism to assist domain experts in constructing thesauri; it determines a considerable part of relationship degrees between terms by inheritance and supplies the domain expert with information available from other parts of the thesaurus being constructed or already constructed. In addition to that, it enables domain experts to incrementally construct the thesaurus, since the automatically determined relationship degrees can be refined whenever a more sophisticated thesaurus is needed. It may minimize domain experts' burden caused by the exhaustive specification of individual relationship. This approach also provides a query-based browsing facility, which enables users to find desired thesaurus terms without tedious browsing in the thesaurus. A browsing query can be formulated with terms rather ambiguous, yet capable of deriving the desired terms. This browsing query is useful especially when users want precise results. In other words, it is useful when they want to use only thesaurus terms carefully selected in reformulating Boolean queries. To demonstrate the feasibility of our approach, we fully implemented an object-based thesaurus system, which supports the semiautomatic thesaurus construction and the query-based browsing facility.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Kagiso Mguni ◽  
Yirsaw Ayalew

Software maintenance is an important activity in software development. Some development methodologies such as the object-oriented have contributed in improving maintainability of software. However, crosscutting concerns are still challenges that affect the maintainability of OO software. In this paper, we discuss our case study to assess the extent of maintainability improvement that can be achieved by employing aspect-oriented programming. Aspect-oriented programming (AOP) is a relatively new approach that emphasizes dealing with crosscutting concerns. To demonstrate the maintainability improvement, we refactored a COTS-based system known as OpenBravoPOS using AspectJ and compared its maintainability with the original OO version. We used both structural complexity and concern level metrics. Our results show an improvement of maintainability in the AOP version of OpenBravoPOS.


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