Gel: A Generic Extensible Language

Abstract. Both XML and Lisp have demonstrated the utility of generic syntax for expressing tree-structured data. But generic languages do not provide the syntactic richness of custom languages. Generic Expression Language (Gel) is a rich generic syntax that embodies many of the common syntactic conventions for operators, grouping and lists in widely-used languages. Prefix/infix operators are disambiguated by white-space, so that documents which violate common white-space conventions will not necessarily parse correctly with Gel. With some character replacements and adjusting for mismatch in operator precedence, Gel can extract meaningful structure from typical files in many languages, including Java, CSS, Smalltalk, and ANTLR grammars. This evaluation shows the expressive power of Gel, not that Gel can be used as a parser for existing languages. Gel is intended to serve as a generic language for creating composable domainspecific languages.

Comonotonicity and maximal stop-loss premiums.

Preprint of paper published in: GITTSE 2007 - International Summer School Generative and Transformational Techniques in Software Engineering, 2-7 July 2007, Lecture Notes in Computer Science 5235; doi:10.1007/978-3-540-88643-3_7 The goal of domain-specific languages (DSLs) is to increase the productivity of software engineers by abstracting from low-level boilerplate code. Introduction of DSLs in the software development process requires a smooth workflow for the production of DSLs themselves. This requires technology for designing and implementing DSLs, but also a methodology for using that technology. That is, a collection of guidelines, design patterns, and reusable DSL components that show developers how to tackle common language design and implementation issues. This paper presents a case study in domain-specific language engineering. It reports on a project in which the author designed and built WebDSL, a DSL for web applications with a rich data model, using several DSLs for DSL engineering: SDF for syntax definition and Stratego/XT for code generation. The paper follows the stages in the development of the DSL. The contributions of the paper are three-fold. (1) A tutorial in the application of the specific SDF and Stratego/XT technology for building DSLs. (2) A description of an incremental DSL development process. (3) A domain-specific language for web-applications with rich data models. The paper concludes with a survey of related approaches.Software Computer TechnologyElectrical Engineering, Mathematics and Computer Scienc