XML Goes Native: Run-Time Representations for Xtatic

Xtatic is an extension of C with native support for statically typed XML processing. It features XML trees as built-in values, “tree grep” pattern matching, and an XML-specific type system. An implementation ofXtatic must address a number of issues common to any language supporting a declarative style of XML processing (e.g., XQuery, XSLT, XDuce, CDuce, Xact, Xen, etc.). In particular, it must provide representations for XML trees and textual data that use memory efficiently, support fast pattern matching, and allow maximal sharing of common substructures. We explore alternative representation choices, analyze and measure their performance, and justify the solutions used by the Xtatic implementation.