Abstract
This paper presents pyZtrategic: a library that embeds strategic term rewriting and attribute grammars in the Python programming language. Strategic term rewriting and attribute grammars are two powerful programming techniques widely used in language engineering: The former relies on strategies to apply term rewrite rules in defining large-scale language transformations, while the latter is suitable to express context-dependent language processing algorithms. Thus, pyZtrategic offers Python programmers recursion schemes (strategies) which apply term rewrite rules in defining large scale language transformations. It also offers attribute grammars to express context-dependent language processing algorithms. PyZtrategic offers the best of those two worlds, thus providing powerful abstractions to express software maintenance and evolution tasks. Moreover, we developed several language engineering problems in pyZtrategic, and we compare it to well established strategic programming and attribute grammar systems. Our preliminary results show that our library offers similar expressiveness as such systems, but, unfortunately, it does suffer from the current poor runtime performance of the Python language. © 2024 by SCITEPRESS – Science and Technology Publications, Lda.

Abstract
Tabulation is a well-known technique for improving the efficiency of recursive functions with redundant function calls. A key point in the application of this technique is to identify a suitable representation for the table. In this paper, we propose the use of zippers as tables in the tabulation process. Our approach relies on a generic function zipWithZipper, that makes strong use of lazy evaluation to traverse two zippers in a circular manner. The technique turns out to be particularly efficient when the arguments to recursive calls are closely situated within the function domain. For example, in the case of natural numbers this means function calls on fairly contiguous values. Likewise, when dealing with tree structures, it means functions calls on immediate sub-trees and parent nodes. This results in a concise and efficient zipper-based embedding of attribute grammars.

Abstract
Software is developed using programming languages whose choice is made based on a wide range of criteria, but it should be noted that the programming language selected can affect the quality of the software product. In this paper, we focus on analysing the differences in energy consumption when running certain algorithms that have been developed using different programming languages. Therefore, we focus on the software quality from the perspective of greenability, in concrete in the aspects related to energy efficiency. For this purpose, this study has conducted an empirical investigation about the most suitable programming languages from an energy efficiency perspective using a hardware-based consumption measurement instrument that obtains real data about energy consumption. The study builds upon a previous study in which energy efficiency of PL were ranked using a software-based approach where the energy consumption is an estimation. As a result, no significant differences are obtained between two approaches, in terms of ranking the PL. However, if it is required to have a more realistic knowledge of consumption, it is necessary to use hardware approaches. Furthermore, the hardware approach provides information about the energy consumption of specific DUT hardware components, such as, HDD, graphics card, and processor, and a ranking for each of component is elaborated. This can provide useful information to make a more informed decision on the choice of a PL, depending on several factors, such as the type of algorithms to be implemented, or the effects on power consumption not only in overall, but also depending on specific DUT hardware components.

Abstract
Contrarily to most conventional programming languages where certain symbols are used so as to create non-ambiguous grammars, most recent programming languages allow ambiguity. These ambiguities are solved using disambiguation rules, which dictate how the software that parses these languages should behave when faced with ambiguities. Such rules are highly efficient but come with some limitations - they cannot be further modified, their behaviour is hidden, and changing them implies re-building a parser. We propose a different approach for disambiguation. A set of disambiguation filters (expressed as combinators) are provided, and disambiguation can be achieved by composing combinators. New combinators can be created and, by having the disambiguation step separated from the parsing step, disambiguation rules can be changed without modifying the parser.

Abstract
This paper presents a preliminary study on the energy consumption of two popular web browsers. In order to properly measure the energy consumption of both environments, we simulate the usage of various applications, which the goal to mimic typical user interactions and usage. Our preliminary results show interesting findings based on observation, such as what type of interactions generate high peaks of energy consumption, and which browser is overall the most efficient. Our goal with this preliminary study is to show to users how very different the efficiency of web browsers can be, and may serve with advances in this area of study.

Abstract
Similar to software systems, programming languages evolve substantially over time. Indeed, the community has more recently seen the release of new versions of mainstream languages in shorter and shorter time frames. For instance, the C++ working group has begun to release a new version of the language every 3 years, which now has a greater number of modern C++ features and improvements in modern standards (C++11, C++14, C++17, and C++ 20). Nonetheless, there is little empirical evidence on how developers are transitioning to use modern C++ constructs in legacy systems, and not understanding the trends and reasons for adopting these new modern C++ features might hinder software developers in conducting rejuvenation efforts. In this paper, we conduct an in-depth study to understand the development practices of KDE contributors to evolve their projects toward the use of modern C++ features. Our results show a trend in the widespread adoption of some modern C++ features (lambda expressions, auto-typed variables, and range-based for) in KDE community projects. We also found that developers in the KDE community are making large efforts to modernize their programs using automated tools, and we present some modernization scenarios and the benefits of adopting modern C++ features of the C++ programming language. Our results might help C++ software developers, in general, to evolve C++ legacy systems and tools builders to implement more effective tools that could help in rejuvenation efforts.