by this facility to propagate intermediate results in a top-down direction, it still cannot do it in a bottom-up direction since it is restricted to return only a single tree and such tree cannot be decomposed once created. In this paper, we introduce multi-return macro tree transducers as a mild extension

Macro tree transducers (mtts) are a useful formal model for XML query and transformation languages. In this paper one of the fundamental decision problems on translations, namely the “translation membership problem ” is studied for mtts. For a fixed translation, the translation membership problem

-walking automata and through a macro tree transduction. This two-step approach gives an operational as well as a logical description of the tree sets involved. As an interlude we show that MCFGs can be regarded as a particularly simple attribute grammar. 1 Introduction Algebraic, logical and regular

The aim of this Dagstuhl Seminar was to bring together researchers from various research areas related to the theory and application of tree transducers. Recently, interest in tree transducers has been revived due to surprising new applications in areas such as XML databases, security verification

A tree transducer is a set of mutually recursive functions transforming an input tree into an output tree. Macro tree transducers extend this recursion scheme by allowing each function to be defined in terms of an arbitrary number of accumulation parameters. In this paper, we show how macro tree

implemented as a component in Treebag. Compared to the top-down tree transducer, the macro tree transducer provides a more powerful model of computation. This thesis describes how Treebag is extended with a macro

Abstract Xml documents conceptually are not trees, but forests. Therefore, we extend the concept of macro tree transducers (mtt’s) to a transformation formalism of forests, macro forest transducers (mft’s). We show that mft’s form a strict superset of mtt’s operating on forests (represented

The macro tree transducer can be considered as a system of recursive function procedures with parameters, where the recursion is on a tree (e.g., the syntax tree of a program). We investigate characterizations of the class of tree (tree-to-string) translations which is induced by macro tree

, or XDuce. It is proved that tl, despite its expressiveness, still allows for effective inverse type inference. This result is obtained by means of a translation of tl transformers into compositions of (stay) macro tree transducers.

tree transducer is compared with the macro tree transducer, a well-known model for syntax-directed semantics, with decidable type checking. The 0-pebble tree transducer can be simulated by the macro tree transducer, which, by the first result, implies that (2) τ can be realized by an (n+1)-fold