Claus Brabrand

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Feature-sensitive verification pursues effective analysis of the exponentially many variants of a program family. However, researchers lack examples of concrete bugs induced by variability, occurring in real large-scale systems. Such a collection of bugs is a requirement for goal-oriented research, serving to evaluate tool implementations of(More)
All uses of HTML forms may benefit from validation of the specified input field values. Simple validation matches individual values against specified formats, while more advanced validation may involve interdependencies of form fields. There is currently no standard for specifying or implementing such validation. Today, CGI programmers often use Perl(More)
It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. We observe that there is a simple linguistic characterization of(More)
Software product lines (SPLs) are commonly developed using annotative approaches such as conditional compilation that come with an inherent risk of constructing erroneous products. For this reason, it is essential to be able to analyze SPLs. However, as dataflow analysis techniques are not able to deal with SPLs, developers must generate and analyze all(More)
We present the results of the <bigwig> project, which aimsto design and implement a high-level domain-specific language forprogramming interactive Web services. A fundamental aspect of the development of the World Wide Webduring the last decade is the gradual change from static to dynamicgeneration of Web pages. Generating Web pages dynamically in(More)
We present the metafront tool for specifying flexible, safe, and efficient syntactic transformations between languages defined by context-free grammars. The transformations are guaranteed to terminate and to map grammatically legal input to grammatically legal output. We rely on a novel parser algorithm that is designed to support gradual extensions of a(More)
We describe a static analysis of \bigwig\ programs that efficiently decides if all dynamically computed XHTML documents presented to the client will validate according to the official DTD. We employ two data-flow analyses to construct a graph summarizing the possible documents. This graph is subsequently analyzed to determine validity of those documents. By(More)
A software product line (SPL) encodes a potentially large variety of software products as variants of some common code base. Up until now, re-using traditional static analyses for SPLs was virtually intractable, as it required programmers to generate and analyze all products individually. In this work, however, we show how an important class of existing(More)