Developmental Studies on Software Development Environment Based on Algebraic Specification Method

本课题的研究目的是建立基于代数规格说明方法的软件环境的技术基础。具体研究内容包括：（1）开发一种易于使用的代数规格说明语言;（2）优化代数规格说明的直接实现系统;（3）设计一个编写代数规格说明的集成编辑器;（4）构造一个能够重用规格说明和程序的智能规格说明数据库。（1）设计并实现了一种允许用层次代数规范声明数据类型的过程化程序设计语言UltraC，即：开发了编译器。该编译器可以对代数规格说明模块进行独立编译，从而有效地执行软件开发过程。(2)开发了代数规范的直接实现系统Cdimple。该系统将代数规范转换为C语言程序。由Cdimple生成的程序运行速度很快，足以用于原型设计。Cdimple现在得到了改进，使得生成的程序接受命令来更新给定的规范，并模拟更新后的规范。(3)设计了一个用于编写代数规范的前端系统，但目前正在开发中。(4)开发了一个规范验证工具。它基于结构归纳法。该工具可用于实现规格说明数据库的检索过程，对用代数方法开发软件开发环境具有重要意义。开发工具的经验表明，应该做什么，把软件开发的代数方法，以实际使用。

The purpose of this research project is to establish technical foundation of software environment based on algebraic specification method. Specific research topics are (1) developing an algebraic specification language easy to use, (2) optimizing the direct implementation system of algebraic specifications, (3) designing an integrated editor for writing algebraic specifications, and (4) constructing intelligent data base of specifications which enable to reuse specifications and programs.The results of the researches are as follows: (1) The procedural programming language UltraC which allows to declare data types by hierarchical algebraic specifications is designed and implemented,i.e., the compiler is developed. The compiler can compile algebraic specification modules separatedly, thereby software developing process is efficiently executed.(2) The direct implementation system of algebraic specifications, called Cdimple, is developed. the system transforms algebraic specifications to C language programs. The programs generated by Cdimple run fast sufficiently for the purpose of prototyping. Cdimple is now improved so that thegenerated program accepts commands to update the given specification and simulates the updated specification.(3) A front-end system for writing algebraic specifications is designed, but it is now under development.(4) A tool for verifying specifications is developed. it is based on structural induction scheme. The tool can be used to implement retrieving procedure of specification data base.The tools mentioned above will play important roles in developing software development environment through the algebraic approach. Experience of developing the tools makes clear what should be done to put algebraic method of software development to practical use.