Web Queries with Style: Rendering Xcerpt Programs with CSSNG

Styling and formatting of XML documents for various target media is often specified with the Cascading Style Sheet (CSS) language. An appealing feature of CSS is that it specifies formatting instructions using rather simple guarded rules. A limitation of CSS is that it focuses on static formatting rules. As a consequence scripting languages such as ECMA Script are used in practice for dynamic adaptation of formatting. CSS is a novel extension of CSS 3, the newest version of CSS, introducing just a few rules for a dynamic rendering and for markup visualization. This limited extension of CSS 3 turns out to make possible a rather advanced visualization of programs. This article (1) introduces into the extensions of CSS with respect to CSS 3, (2) describes a proof-of-concept prototype implementation of CSS, and (3) demonstrates CSS on Xcerpt query programs.