Abstract

Abstract
This paper presents techniques for a component-based style of programming in the context of higher-oder attribute grammars (HAG). Attribute grammar components are "plugged in" into larger attribute grammar systems through higher-order attribute grammars. Higher-order attributes are used as (intermediate) "gluing" data structures. This paper also presents two attribute grammar components that can be re-used across different language-based tool specifications: a visualizer and animator of programs and a graphical user interface AG component. Both components are reused in the definition of a simple language processor. The techniques presented in this paper are implemented in LRC: a purely functional, higher-order attribute grammar-based system that generates language-based tools.

Abstract
Graphical user interfaces (GUIs) are critical components of todays software. Given their increased relevance, correctness and usability of GUIs are becoming essential. This paper describes the latest results in the development of our tool to reverse engineer the GUI layer of interactive computing systems. We use static analysis techniques to generate models of the user interface behaviour from source code. Models help in graphical user interface inspection by allowing designers to concentrate on its more important aspects. One particular type of model that the tool is able to generate is state machines. The paper shows how graph theory can be useful when applied to these models. A number of metrics and algorithms are used in the analysis of aspects of the user interface's quality. The ultimate goal of the tool is to enable analysis of interactive system through GUIs source code inspection. © 2010, Universitatsbibliothek TU Berlin.

Abstract
Functional programs often combine separate parts using intermediate data structures for communicating results. These programs are modular, easier to understand and maintain, but suffer from inefficiencies due to the generation of those gluing data structures. To eliminate such redundant data structures, some program transformation techniques have been proposed. One such technique is shortcut fusion, and has been studied in the context of both pure and monadic functional programs. Recently, we have extended standard shortcut fusion: in addition to intermediate structures, the program parts may now communicate context information, and it still is possible to eliminate those structures. This is achieved by transforming the original function composition into a circular program. This new technique, however, has been studied in the context of purely functional programs only. In this paper, we propose an extension to this new form of fusion,but in the context of monadic programming: we derive monadic circular p ograms from strict ones, maintaining the global effects. Later, the circularities in the derived programs are traded by highorder definitions, using a well-known program transformation technique. We finally obtain very efficient deforested programs. An important feature of our extensions is that they can beuniformly defined for a wide class of data types and monads, using generic calculation rules. ©2009 ACM.

Abstract
This paper presents a technique to construct compilers expressed in a strict, purely functional setting. The compilers do not rely on any explicit data structures, like trees, stacks or queues, to efficiently perform the compilation task. They are constructed as a set of functions which are directly called by the parser. An abstract syntax tree is neither constructed nor traversed. Such deforestated compilers are automatically derived from an attribute grammar specification. Furthermore this technique can be used to efficiently implement any multiple traversal algorithm.

Abstract
This paper presents a new strict, purely functional implementation of attribute grammars. Incremental evaluation is obtained via standard function memoization. Our new implementation of attribute grammars increases the incremental behaviour of the evaluators by both reducing the memoization overhead and increasing their potential incrementallity. We present also an attribute grammar transformation, which increases the incremental performance of the attribute evaluators after a change that propagates its effects to all parts of the syntax tree. These techniques have been implemented in a purely functional attribute grammar system and the first experimental results are presented.