A Case for Custom, Composable Composition Operators

Programming languages typically support a fixed set of com- position operators, with fixed semantics. This may impose limits on software designers, in case a desired operator or semantics are not supported by a language, resulting in suboptimal quality characteristics of the designed software system. We demonstrate this using the well-known State design pattern, and propose the use of a composition infrastructure that allows the designer to define custom, composable composition operators. We demonstrate how this approach improves several quality factors of the State design pattern, such as reusability and modularity, while taking a reason- able amount of effort to define the necessary pattern-related code

Copy-paste Tracking: Fixing Spreadsheets Without Breaking Them

Spreadsheets are the most popular live programming environments, but they are also notoriously fault-prone. One reason for this is that users actively rely on copy-paste to make up for the lack of abstraction mechanisms. Adding abstraction however, introduces indirection and thus cognitive distance. In this paper we propose an alternative: copy-paste tracking. Tracking copies that spreadsheet users make, allows them to directly edit copy-pasted formulas, but instead of changing only a single instance, the changes will be propagated to all formulas copied from the same source. As a result, spreadsheet users will enjoy the benefits of abstraction without its drawbacks

Edition synchrone de plusieurs objets : services et interaction

International audienceGraphical interactions that modify many objects at once have not been studied systematically. Based on contextual inquiries of designers, and on previous systems and work, we have identified the services required for an efficient interaction with multiple objects: set management, action management, and support for exploratory design. We present a number of interactions that provide a subset of the identified services, by relying on an improved property sheet. This work may enable designers to design more consistent and more powerful interactions

Copy-Paste Tracking: Fixing Spreadsheets Without Breaking Them

International audienceSpreadsheets are the most popular live programming environments, but they are also notoriously fault-prone. One reason for this is that users actively rely on copy-paste to make up for the lack of abstraction mechanisms. Adding abstraction however, introduces indirection and thus cognitive distance. In this paper we propose an alternative: copy-paste tracking. Tracking copies that spreadsheet users make, allows them to directly edit copy-pasted formulas, but instead of changing only a single instance, the changes will be propagated to all formulas copied from the same source. As a result, spreadsheet users will enjoy the benefits of abstraction without its drawbacks

Copy-paste tracking: Fixing spreadsheets without breaking them

Spreadsheets are the most popular live programming environments, but they are also notoriously fault-prone. One reason for this is that users actively rely on copy-paste to make up for the lack of abstraction mechanisms. Adding abstraction however, introduces indirection and thus cognitive distance. In this paper we propose an alternative: copy-paste tracking. Tracking copies that spreadsheet users make, allows them to directly edit copy-pasted formulas, but instead of changing only a single instance, the changes will be propagated to all formulas copied from the same source. As a result, spreadsheet users will enjoy the benefits of abstraction without its drawback.FWN – Publicaties zonder aanstelling Universiteit Leide

ELICITIATION OF INFORMATICS ENGINEERING INFOTECH WEBSITE NEEDS USING A USER PERSONA APPROACH

Requirements elicitation is the most important activity in the software development process, because it has a direct impact on the success of the development process. The success of a software is determined from the involvement of a user persona at the design stage. The involvement of user personas in software design is critical in the requirements engineering process, because if the process is done incorrectly, the resulting software will also have poor quality. This study focuses on using the approach of the user persona in collecting information related to the needs of the informatics engineering infotech website at the University of Muhammadiyah Malang, so that the results obtained can be in accordance with the needs of the user. The final result that is expected in this research is a design of the plagiarism check feature for the practitioner's program automatically on the infotech website which is implemented in the form of use cases and prototypes. This feature will later make it easier for assistants in assessing program results collected by practitioners, so that the time needed to correct the program can be done faster

An Object Model for Shared Data

The classical object model supports private data within objects and clean interfaces among objects, and by definition does not permit sharing of data among arbitrary objects. This is a problem for certain real-world applications, where the same data logically belongs 10 multiple objects and may be distributed over multiple nodes on the network. Rather than give up the advantages of encapsulated objects in modeling real-world entities, we propose a new object model that supports shared data in a distributed environment. The key is separating distribution of computation units from information hiding concerns. We introduce our new object model, describe a motivating example from the financial services domain, and then present a new language, PROFIT, based on the model

Design Issues in a Minimal Language to Support Lisp-based, Object-based, and Rule-based Programming

13 pagesIn this paper we argue for a minimalist view of language design for Expert System environments. In support of our arguments we present MIN, a minimal language which extends the less-is-better philosophy of Scheme to include both object-based and rule-based components. We discuss the strengths and weaknesses of MIN as an embodiment of the minimalist philosophy, and point to other work supporting this view of language design