Showing papers on "Tree-adjoining grammar published in 1982"
TL;DR: Attributed programmed graph grammars are introduced in this paper and their application to the interpretation of schematic diagrams is proposed.
Abstract: Attributed programmed graph grammars are introduced in this paper and their application to the interpretation of schematic diagrams is proposed. In contrast with most of the approaches to syntactic pattern recognition, where the grammar controls a parser, the grammar in our system is used as a generative tool. Two classes of diagrams are studied, namely circuit diagrams and flowcharts. The task is in either case to extract a description from an input diagram.
162 citations
TL;DR: This paper considers a possible classification of embedding mechanisms for (node-rewriting) graph grammars, which allows one to fit a number of existing notions of a graph grammar into a common framework and points out new “natural” possibilities for defining the embedding mechanism in a graph Grammar.
89 citations
04 Oct 1982
TL;DR: This paper presents a formalization of the notion graphic, which is considered to consist of an ordinary graph describing the overall structure and a set of attributes describing the shape, placement, etc. of the nodes and edges of the underlying graph.
Abstract: This paper presents a formalization of the notion graphic. A graphic is considered to consist of an ordinary graph describing the overall structure and a set of attributes describing the shape, placement, etc. of the nodes and edges of the underlying graph. The formal handling of graphics is done by attributing the rules of graph grammars and by passing the attributes up and down the derivation tree of the graphic.
70 citations
TL;DR: Two embedding mechanisms used in graph grammars are discussed and compared: a connection relation mechanism ( introduced in Janssens and Rozenberg) and a stencil mechanism (introduced in Culik and Lindenmayer).
45 citations
04 Oct 1982
TL;DR: In this paper, the authors define grammars on a class of labeled, partially ordered hypergraphs, called distributed systems, and define rewriting rules to model the synchronized evolution of adjacent system components.
Abstract: In the paper we define grammars on a class of labeled, partially ordered hypergraphs, called distributed systems. A distributed system models both the spatial and the temporal aspects of a real system through the relations of adjacency and causality. Terminal symbols represent the (deterministic, certain) past history of the system while nonterminal symbols model the (possibly nondeterministic, potential) future history of the system. The (context free) productions of a grammar represent the possible stand-alone evolutions of system components. From the productions, we obtain a (possibly infinite) number of rewriting rules, which model the synchronized evolution of adjacent system components. The (terminal) distributed systems derived within a given grammar represent the alternative deterministic, concurrent computations of a single nondeterministic system which is thus completely modeled by the grammar.
39 citations
38 citations
04 Oct 1982
36 citations
23 citations
04 Oct 1982
TL;DR: It is proposed to combine the new approach of Ugo Montanari for synchronization with the aspects of concurrency reviewed above to obtain a graph grammar based model for concurrent and distributed systems.
Abstract: This paper is a written version of the overview lecture on “Concurrency in Graph Grammars” given at the “2nd International Workshop on Graph Grammars and their Applications to Computer Science, 1982”. The intention of that lecture and this paper is to show that a number of results in the transformational theory of graph grammars can be considered already as contributions towards a theory of concurrency in graph grammars. Simulations of Petri nets within graph grammars are reviewed and simulations of algebraic specifications within graph grammars are introduced to cover also abstract data type concepts. More general concepts of concurrency are considered to be studied in the framework of graph grammars which go essentially beyond those in Petri nets. Finally it is proposed to combine the new approach of Ugo Montanari for synchronization with the aspects of concurrency reviewed above to obtain a graph grammar based model for concurrent and distributed systems.
18 citations
TL;DR: It is shown that the equivalence problem for LL-regular grammars is decidable by reducing it to the equivalences problem for real-time strict deterministic Grammars.
13 citations
04 Oct 1982
TL;DR: In this article, a graph grammars are used to specify, in a very general way, the evaluators which are generated from atgs, and specify meaningful parsers and compilers if the atgs satisfy some weak conditions.
Abstract: Attribute grammars (atgs, for short) are string rewriting systems, allowing programming languages to be defined together with their context conditions and translations. In this paper graph grammars are used to specify, in a very general way, the evaluators which are generated from atgs. These graph grammars are correct with respect to the languages derived by atgs, and specify meaningful parsers and compilers if the atgs satisfy some weak conditions.
TL;DR: The main results are that each context-free language is defined by a grammar G of any desired position-restricted type, and that all languages in L(G1) are defined by an interpretation grammars of G2 of position- restricted type.
09 Mar 1982
TL;DR: The concepts of L- and LR-attributed grammar are extended to attributed grammars with an underlying regular right part grammar.
Abstract: The L-attributed grammars form an attractive subclass of attribute grammars since the test for L~attributedness is cheap and attribute evaluation can be done in one left-to-right depth-first traversal of the syntax tree. Still more attractive are subclasses of L-attributed grammars which allow parser-directed attribute evaluation. Two such classes called LL- and LR-attributed grammars, are supported by the compiler generating system MUG 1 (WRC 76, Gan 76). Their implementation is described in the LR~case based on work by Watt (Wat 74,77). The concepts of L- and LR-attributed grammar are extended to attributed grammars with an underlying regular right part grammar.
TL;DR: This work shows that the flag strings generated by indexed grammars are regular sets and can be generated by regular canonical systems, and generates all the deterministic contextfree languages, along with some noncontextfree languages.
Abstract: This dissertation presents a new algorithm for parsing left-corner context-free grammars and develops extensions of context-free parsing concepts to indexed grammars. It presents a complete definition and algorithms for a class of indexed LL-parsable (ILL) grammars. These parsers are based on two-level pushdown automata. It also reports some of the problems in trying to extend left-corner techniques to indexed grammars. It includes an extensive bibliography of extensions to context-free grammars.
TL;DR: It is shown that it is possible to transform any LL-regular grammar G into an LL(1) grammar G' in such a way that parsing G' is as good as parsing G.
Abstract: In this paper it is shown that it is possible to transform any LL-regular grammar G into an LL(1) grammar G' in such a way that parsing G' is as good as parsing G. That is, a parse of a sentence of grammar G can be obtained with a simple string homomorphism from the parse of a corresponding sentence of G'. Since any LL(k) grammar is an LL-regular grammar the results that are obtained are valid for LL(k) grammars as well. The relation between LL-regular grammars is expressed by means of a generalized version of the well-known cover relation between two grammars.
TL;DR: A new type of formal grammars where the derivation process is regulated by a certain function which evaluates the words can be regarded as a model for the molecular replication process with selective character.
TL;DR: It is shown that the generative power of k - linear ( k ⩾ 1) grammars is increased by composition, and it is of interest to note that the families of compound linear and compound k -linear languages are equal.
TL;DR: Minimal grammar-dependent upper bounds are determined both on the derivational time complexity, that is, the number of derivation steps needed to derive a sentence of given length, and on the derived space complexity, the length of the longest sentential form needed in the derivation.
Abstract: Derivational complexity of context-free grammars is studied. Minimal grammar-dependent upper bounds are determined both on the derivational time complexity, that is, the number of derivation steps needed to derive a sentence of given length, and on the derivational space complexity, that is, the length of the longest sentential form needed in the derivation. In addition to general context-free grammars, these upper bounds are also determined specifically for ɛ -free grammars, non-left-recursive and non-right-recursive grammars, and for LL( k ) grammars. The results might prove useful in parser optimization, because the complexity of a parser is closely related to the derivational complexity of the underlying context-free grammar.
12 Jul 1982
TL;DR: In the literature various proofs of the inclusion of theclass of LL(k) grammars into the class of LR(k), some are correct but the proof is less straightforward than demonstrated here.
Journal Article•
01 Apr 1982
TL;DR: A class of context-free grammars, called "Extended LL(k)" or ELL(k), is defined, and it has been shown to include LL( k) grammARS as proper subset, and there are some Grammars which are ELL (k)grammars but not LALR(k) gramMars.
Abstract: A class of context-free grammars, called "Extended LL(k)" or ELL(k), is defined. This class has been shown to include LL(k) grammars as proper subset, and there are some grammars which are ELL(k) grammars but not LALR(k) grammars.An algorithm to construct persers for ELL(k) grammars is proposed in this paper.Before this paper had been completed, PL/O language was taken as a sample. A parser was constructed for it by ELL(k) technique.
TL;DR: A syntax-directed interpreter of attribute Grammars is applied to interpret meta grammars describing translators to help clarify the role of interpreters in the development of knowledge representation.
Abstract: A syntax-directed interpreter of attribute grammars is applied to interpret meta grammars describing translators. A specific example is used which concerns the formal description of the same syntax-directed interpreter of attribute grammars for illustration of our approach.
05 Jul 1982
TL;DR: It is shown that a loop-free tree directed grammar can be transformed into an equivalent top-down tree transducer, and from this fact it follows that given an arbitrary context-free language as input, a treedirected grammar produces an output language which is at most context-sensitive.
Abstract: Tree directed grammars as a special kind of translation grammars are defined. It is shown that a loop-free tree directed grammar can be transformed into an equivalent top-down tree transducer, and from this fact it follows that given an arbitrary context-free language as input, a tree directed grammar produces an output language which is at most context-sensitive.
TL;DR: This paper demonstrates that the metalinguistic formalism of two-level grammars' application to low-level control facilities—labels and goto statements—is not only possible but also reasonably straightforward and manageable.
Abstract: The metalinguistic formalism of two-level grammars (W-grammars) is known to be capable of precisely defining the dynamic semantics of certain features of programming languages in a fairly understandable fashion. This paper demonstrates that its application to low-level control facilities—labels and goto statements—is not only possible but also reasonably straightforward and manageable. Moreover, the extra definitional complexity that arises when there is a mixture of low-level and high-level (if-then-else, while-do, etc.) facilities does not appear to be any worse than it is with other approaches to semantic specification.
TL;DR: It is shown that any two acyclic deterministic pure (dP) grammars that generate the same finite language are isomorphic and that the form-equivalence problem for dP grammar forms is decidable.
TL;DR: A large subclass of LR( k) grammars, called predictive LR(k) or PLR(k), is considered in terms of the compilation activities a PLR (k) parser can drive, and its properties are measured by defining a class of syntax-directed translations defined by a deterministic pushdown transducer.
Abstract: A large subclass of LR(k) grammars, called predictive LR(k) or PLR(k) grammars, is considered in terms of the compilation activities a PLR(k) parser can drive. These properties are measured by defining for PLR(k) grammars a class of syntax-directed translations definable by a deterministic pushdown transducer.