Lyntax - A grammar-Based Tool for Linguistics

This paper is focused on using the formalism of attribute grammars to create a tool that allows Linguistic teachers to construct automatically their own processors totally adapted to each linguistic exercise. The system developed, named Lyntax, is a compiler for a domain specific language which intends to enable the teacher to specify different kinds of sentence structures, and then, ask the student to test his own sentences against those structures. The processor Lyntax validates the grammar (DSL program) written by the teacher, generating a processor every time the student defines a new sentence. For that ANTLR is used in both steps, generating not only the specialized processor but also the visualization of the syntax tree for analysis purposes. An interface that supports the specification of the language was built, also allowing the use of the processor and the generation of the specific grammar, abstracting the user of any calculations

Applying attribute grammars to teach linguistic rules

Dissertação de mestrado integrado em Engenharia InformáticaThis document presents the topic “Applying Attribute Grammars to teach Linguistic Rules”, at Universidade do Minho in Braga, Portugal. This thesis is focused on using the formalisms of attribute grammars in order to create a tool to help linguistic students learn the different rules of a natural language. The system developed, named Lyntax, consists in a processor for a domain specific language which intends to enable the user to specify different kinds of sentence structures, and afterwards, test various phrases against said structures. The processor validates and evaluates the input given, generating a grammar which is specific to a previously chosen sentence. Lastly, using ANTLR, a parser is generated for that specific grammar referred above. The processor built by ANTLR also creates a syntax tree that is presented to the user for analysis purposes. An interface that supports the specification of the language (written in Lyntax DSL) was built, also allowing the use of the processor and the generation of the specific grammar, exempting the user from knowing the details of the process. Within this document, the focus will be primarly dedicated to the analysis of the system and how each block was built. Different examples of the processor in action will be shown and explained.Este documento refere-se a uma dissertação sobre o tópico “Aplicar Gramáticas de Atribu tos no ensino de Regras de Linguística”, e será concluída na Universidade do Minho em Braga, Portugal. Esta dissertação pretende focar-se no uso dos formalismos das gramáticas de atributos de maneira a criar uma ferramenta que ajude os alunos de linguística a aprender as diversas regras da língua natural. O sistema desenvolvido, denominado de Lyntax, consiste em um processor para uma linguagem de domínio específico cujo objetivo é o de permitir ao seu utilizador a possibili dade de especificar diversas estruturas de frases, e posteriormente, testar frases contra essas mesmas estruturas. O processador valida e avalia o input recebido, gerando uma gramática específica à frase previamente escolhida. Por fim, usando uma ferramenta como o ANTLR, um parser é gerado para a gramática específica acima referida. O processador construído pelo ANTLR também gera a árvore de syntax que é apresentada ao utilizador com o intuito de ser analisada. Foi também criada uma interface que suporta a especificação da linguagem, permitindo também o uso do processador e a geração da gramática específica, abstraindo assim o utilizador de quaisquer tipo de cálculos. Neste documento, o focus primário será dedicado à análise do sistema e como cada bloco foi construído. Diferentes exemplos de uso do processador serão apresentados e explicados

Zipper-based embedding of modern attribute grammar extensions

This research abstract describes the research plan for a Ph.D project. We plan to define a powerful and elegant embedding of modern extensions to attribute grammars. Attribute grammars are a suitable formalism to express complex, multiple traversal algorithms. In recent years there has been a lot of work in attribute grammars, namely by defining new extensions to the formalism (forwarding and reference attribute grammars, etc), by proposing new attribute evaluation models (lazy and circular evaluators, etc) and by embedding attribute grammars (like first class attribute grammars). We will study how to design such extensions through a zipper-based embedding and we will study eficient evaluation models for this embedding. Finally, we will express several attribute grammars in our setting and we will analyse the performance of our implementation.(undefined

Feature-based and Model-based Semantics for English, French and German Verb Phrases

This paper considers the relative merits of using features and formal event models to characterise the semantics of English, French and German verb phrases, and con- siders the application of such semantics in machine translation. The feature-based ap- proach represents the semantics in terms of feature systems, which have been widely used in computational linguistics for representing complex syntactic structures. The paper shows how a simple intuitive semantics of verb phrases may be encoded as a feature system, and how this can be used to support modular construction of au- tomatic translation systems through feature look-up tables. This is illustrated by automated translation of English into either French or German. The paper contin- ues to formalise the feature-based approach via a model-based, Montague semantics, which extends previous work on the semantics of English verb phrases. In so doing, repercussions of and to this framework in conducting a contrastive semantic study are considered. The model-based approach also promises to provide support for a more sophisticated approach to translation through logical proof; the paper indicates further work required for the fulfilment of this promise

Metamodel Instance Generation: A systematic literature review

Modelling and thus metamodelling have become increasingly important in Software Engineering through the use of Model Driven Engineering. In this paper we present a systematic literature review of instance generation techniques for metamodels, i.e. the process of automatically generating models from a given metamodel. We start by presenting a set of research questions that our review is intended to answer. We then identify the main topics that are related to metamodel instance generation techniques, and use these to initiate our literature search. This search resulted in the identification of 34 key papers in the area, and each of these is reviewed here and discussed in detail. The outcome is that we are able to identify a knowledge gap in this field, and we offer suggestions as to some potential directions for future research.Comment: 25 page

The perimeter generating functions of three-choice, imperfect, and 1-punctured staircase polygons

We consider the isotropic perimeter generating functions of three-choice, imperfect, and 1-punctured staircase polygons, whose 8th order linear Fuchsian ODEs are previously known. We derive simple relationships between the three generating functions, and show that all three generating functions are joint solutions of a common 12th order Fuchsian linear ODE. We find that the 8th order differential operators can each be rewritten as a direct sum of a direct product, with operators no larger than 3rd order. We give closed-form expressions for all the solutions of these operators in terms of $_2F_1$ hypergeometric functions with rational and algebraic arguments. The solutions of these linear differential operators can in fact be expressed in terms of two modular forms, since these $_2F_1$ hypergeometric functions can be expressed with two, rational or algebraic, pullbacks.Comment: 28 page