© 2001 by British Computer Society
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A Context-sensitive Graph Grammar Formalism for the Specification of Visual Languages
1 Coral Corporation, 1600 Carling Avenue, Ottawa, Canada Email: kzhang@utdallas.edu 2 Department of Computer Science, Box 830688, MS EC31, University of Texas at Dallas, Richardson, Texas 75083-0688, USA 3 Department of Computing, Hong Kong Polytechnic University, Kowloon, Hong Kong 4 Author for correspondence.
Graph grammars may be used as natural and powerful syntax-definition formalisms for visual programming languages. Yet most graph-grammar parsing algorithms presented so far are either unable to recognize interesting visual languages or tend to be inefficient (with exponential time complexity) when applied to graphs with a large number of nodes and edges. This paper presents a context-sensitive graph grammar called reserved graph grammar, which can explicitly and completely describe the syntax of a wide range of diagrams using labeled graphs. The parsing algorithm of a reserved graph grammar uses a marking mechanism to avoid ambiguity in parsing and has polynomial time complexity in most cases. The paper defines a constraint condition under which a graph defined in a reserved graph grammar can be parsed in polynomial time. An algorithm for checking the condition is also provided.
Received 25 May, 2001. Revised 19 March, 2001.