The Progres Approach: Language and Environment

Abstract

Graphs play an important role within many areas of computer science. Rule-based languages, on the other hand, are well-suited for the description of transformation or inference processes on complex data structures. Why not combining two successful principles in one formalism? This is the common vision of the graph transformation community and the main motivation behind the development of PROGRES, a visual language that supports PROgramming with Graph REwriting Systems. The language PROGRES was developed having the following three design goals in mind: (1) Distinguish between data de nition and manipulation activities and use graph schemata to type-check graph transformation rules. (2) Do not rely on the rule-oriented paradigm for all purposes, but support also imperative programming with control structures. (3) Refrain users from the task to guarantee con uence of de ned rules by keeping track of rewriting con icts and backtracking out of dead-end derivations. Its accompanying programming environment o ers assistance for creating, analyzing, compiling, and debugging graph transformations as well as for rapid prototyping activities. Being an integrated set of tools with support for intertwining these activities, it combines the exibility of interpreted languages with the safeness of compiled and statically typed languages.

A graph-based algorithm for consistency maintenance in incremental and interactive integration tools

“…In the case of the IREEN prototype presented in Sect. 4.2, the PROGRES environment generates fast code from graph transformation rules by employing sophisticated heuristics for graph pattern matching [35]. In the C++ framework presented in Section 9, the integration algorithm was implemented even more efficiently by exploiting specific properties of the integrator rule set and by hard-coding the domain-independent core part of the integration algorithm.…”

“…As a notation for graph grammars and graph transformation systems, we will use the specification language PROGRES [35]. We have specified our graph algorithm for incremental and interactive consistency maintenance with the help of the PROGRES development environment, which offers -among other tools such as a syntax-aided editor and an interpreter -a compiler which generates code from the specification.…”

“…The rule-specific graph transformation rules are automatically derived from the forward, backward, and correspondence analysis rules using a code generator. The generator output is an incomplete specification of a graph transformation system for the PROGRES system [35] containing the specific graph transformation rules for each integration rule. The translation of integration rules into the rule-specific graph transformation rules is not formally specified in this paper.…”

“…The complete specification is compiled by the PROGRES system [35] resulting in C code which is then embedded into the UPGRADE framework which provides a graphical user interface and persistent graph storage for the generated code [8]. This leads to a prototype which allows construction and modification of source and target graphs as well as simulating runs of the integration tool.…”

Behaviour Protection in Modular Rule-Based System Specifications

“…For example, Große-Rhode, Parisi-Presicce, and Simeoni introduce in [22] a notion of module for typed graph transformation systems, with interfaces and implementation bodies; they propose operations for union, composition, and refinement of modules. Other approaches to modularisation of graph transformation systems include PROGRES Packages [42], GRACE Graph Transformation Units and Modules [31], and DIEGO Modules [43]. See [26] for a discussion on these proposals.…”