一个基于混合模型的用户界面管理系统的设计和实现

1.引言 用户界面及其管理系统的研究逐渐成为计算机图形学中一个颇受重视的课题,Siggraph在1982年召开的GIIT专题会上阐明了用户界面管理系统(UIMS)的基本概念,并于1986年在西雅图召开的“用户界面管理软件工具”专题讨论中对该领域进行了深入的讨论,目前广泛采用的Seeheim模型把用户界面分成表示元素、对话控制和应用接口模型三个部分,其核心对话控制通常采用转移网络、上下文无关文法及事件等三种基本模型     

网络通信协议的属性文法规格说明

本文给出一个基于属性文法的网络通信协议的形式说明与自动生成的模型.首先引入了一个扩展的属性文法描述工具,讨论了用其描述协议的并行、同步、延时（时序）等特性的有关问题；然后研究了基于属性文法的网络通信协议自动生成环境及其核心算法——属性计算（即语义分析）算法.     

属性文法的研究与应用

本文详细讨论了有关属性文法的基本概念,属性文法的两种分类方法,两种分类之间的关系及属性文法的判定问题。本文还讨论了如何用属性文法定义编译程序的遍体制说明及与指称语义的关系。最后讨论了属性文法在编译程序中的应用与属性计算器的程序处理。     

基于属性文法和语义网络的综合知识表示模型

本文提出了一个属性文法计算模型与语义网络表示模型相结合的综合知识表示模型.根据形式化的语义网络表示模型和属性文法的特点,该模型使用属性文法的符号建立了一些适合于语义网络表示模型的语法和语义规则模式,并且可通过扩充的属性文法的解释器来实现推理.     

FORTRAN语言的一个属性文法

本文介绍了用属性定义语言ALADIN写的FORTRAN语言的属性文法。该文法描述了FORTRAN语言的语法结构及其静态语义,包括作用域规则、说明的建立、表达式分析和出错处理等。     

综合知识表示模型MAS的属性文法推理机制

根据文献［２］中提出了的基于属性文法和语义网络的综合知识表示模型ＭＡＳ，本文提出了关于实现该ＭＡＳ推理机制的基本算法，并且通过实例对该算法进行了说明，最后，证明了基于ＭＡＳ模板的属性文法是Ｌ－ＡＧ和ＩＭＡＳ的解是完全的结论。     

一个基于属性文法的通信协议形式描述语言及协议开发环境

通信协议是网络技术的核心。由于异质构环境中网络协议固有的复杂性,因此需要研制一磁建立在严格数学模型基础这之上的协议开发方法和集成工具环境,以降低协议开发难度,提高协议开发效率。本文旨在探索一种用于协议形式描述和工程开发的扩展属性文法,重点研究了设计属性文法描述语言的原理及结构特点等,并通过一个完整例子说明如何使用我们所设计的属性文法描述语言Ｌ＿ＰＳＡＧ定义一个协议,然后给出一个基于属性文法的协议设     

AGDL——一个属性文法定义语言

AGDL是一个属性文法定义语言,用来进行编译程序自动生成的说明。AGDL具有抽象数据类型的定义的施用型(Applicative language)语言,因此属性文法规则简明易读,是用来发展编译程序生成的重要工具语言。     

编译程序的范式结构及用属性文法进行编译程序设计(下)

4.用属性文法进行编译程序设计近些年属性文法得到广泛的发展与应用.用属性文法进行编译程序设计可以是工具的辅助设计,也可以是人工进行设计.我们在这里主要介绍程序员如何根据属性文法的定义进行编译程序设计,并假定读者对属性文法的基本概念已经清楚.4.1属性文法的分类及判定问题     

An Approach to User Interface Specification with Attribute Grammars

An approach to supporting user interfaces using an attribute grammar combined with an event model is described.The main emphasis is how to represent a multi-thread dialogue model in direct manipulation user interfaces.It is shown that control sequence within dialogues,communication with other dialogues, and some computations for applications can be specified with a syntactic and semantic notation.The attribute grammar specification can be implemented using an attribute grammar intepreter embedded in the run-time structure supporting communication,synchronization,and dialogue executon.     

Monolithic and modular termination analyses for higher-order attribute grammars

In this paper we describe a sound, but not complete, analysis to prove the termination of higher-order attribute grammar evaluation caused by the creation of an unbounded number of (finite) trees as local tree-valued attributes, which are then themselves decorated with attributes. The analysis extracts a set of term-rewriting rules from the grammar that model creation of new syntax trees during the evaluation of higher-order attributes. If this term rewriting system terminates, then only a finite number of trees will be created during attribute grammar evaluation. The analysis places an ordering on nonterminals to handle the cases in which higher-order inherited attributes are used to ensure that a finite number of trees are created using such attributes. When paired with the traditional completeness and circularity analyses for attribute grammars and the assumption that each attribute equation defines a terminating computation, this analysis can be used to show that attribute grammar evaluation will terminate normally. This analysis can be applied to a wide range of common attribute grammar idioms and has been used to show that evaluation of our specification of Java 1.4 terminates. We also describe a modular version of the analysis that is performed on independently developed language extension grammars and the host language being extended. If the extensions individually pass the modular analysis then their composition is also guaranteed to terminate.     

Simple multi-visit attribute grammars

An attribute grammar is simple multi-visit if each attribute of a nonterminal has a fixed visit-number associated with it such that, during attribute evaluation, the attributes of a node which have visit-number j are computed at the jth visit to the node. An attribute grammar is l-ordered if for each nonterminal a linear order of its attributes exists such that the attributes of a node can always be evaluated in that order (cf. the work of Kastens).An attribute grammar is simple multi-visit if and only if it is l-ordered. Every noncircular attribute grammar can be transformed into an equivalent simple multi-visit attribute grammar which uses the same semantic operations.For a given distribution of visit-numbers over the attributes, it can be decided in polynomial time whether the attributes can be evaluated according to these visit-numbers. The problem whether an attribute grammar is simple multi-visit is NP-complete.     

A classification of noncircular attribute grammars based on thelook-ahead behavior

We propose a family of static evaluators for subclasses of the well-defined (i.e., noncircular) attribute grammars. These evaluators augment the evaluator for the absolutely noncircular attribute grammars with look-ahead behaviors. Because this family covers exactly the set of all well-defined attribute grammars, well-defined attribute grammars may be classified into a hierarchy, called the NC hierarchy, according to their evaluators in the family. The location of a noncircular attribute grammar in the NC hierarchy is an intrinsic property of the grammar. The NC hierarchy confirms a result of Riis and Skyum (1981), which says that all well-defined attribute grammars allow a (static) pure multivisit evaluator by actually constructing such an evaluator. We also show that, for any finite m, an NC(m) attribute grammar can be transformed to an equivalent NC(0) grammar     

The formal power of one-visit attribute grammars

Summary An attribute grammar is one-visit if the attributes can be evaluated by walking through the derivation tree in such a way that each subtree is visited at most once. One-visit (1V) attribute grammars are compared with one-pass left-to-right (L) attribute grammars and with attribute grammars having only one synthesized attribute (1S).Every 1S attribute grammar can be made one-visit. One-visit attribute grammars are simply permutations of L attribute grammars; thus the classes of output sets of 1V and L attribute grammars coincide, and similarly for 1S and L-1S attribute grammars. In case all attribute values are trees, the translation realized by a 1V attribute grammar is the composition of the translation realized by a 1S attribute grammar with a deterministic top-down tree transduction, and vice versa; thus, using a result of Duske e.a., the class of output languages of 1V (or L) attribute grammars is the image of the class of IO macro tree languages under all deterministic top-down tree transductions.     

Silver: an Extensible Attribute Grammar System

Attribute grammar specification languages, like many domain specific languages, offer significant advantages to their users, such as high-level declarative constructs and domain-specific analyses. Despite these advantages, attribute grammars are often not adopted to the degree that their proponents envision. One practical obstacle to their adoption is a perceived lack of both domain-specific and general purpose language features needed to address the many different aspects of a problem. Here we describe Silver, an extensible attribute grammar specification language, and show how it can be extended with general purpose features such as pattern matching and domain specific features such as collection attributes and constructs for supporting data-flow analysis of imperative programs. The result is an attribute grammar specification language with a rich set of language features. Silver is implemented in itself by a Silver attribute grammar and utilizes forwarding to implement the extensions in a cost-effective manner.