Visual Occam: Syntax and semantics

doi:10.1016/S0096-0551(97)00005-2

Computer Languages

Volume 23, Issue 1, April 1997, Pages 1-24

https://doi.org/10.1016/S0096-0551(97)00005-2 Get rights and content

Abstract

Visual Occam (VISO) is a visual programming language for concurrent programming. It uses message passing for interprocess communication and processes are disjoint. The VISO language uses a modular approach to visual programming which simplifies the specification of programs. It has a graphical syntax based on the language Occam. The petri net formalism is used to represent the semantics of the VISO language. This paper describes the design and implementation of the VISO language. It presents syntax, semantics, and a number of concurrent programs specified in the VISO language. Also, it discusses how synchronous communication can be expressed in petri nets.

References (11)

M. Pong
I-pigs: an interactive graphical environment for concurrent programming
The Computer Journal
(1991)
J. Kramer et al.
Graphical configuration programming
IEEE Computer
(1989)
J. Magee et al.
Structuring parallel and distributed programs
Software Engineering Journal
(1993)
R. Mario et al.
Durra, a structure description language for developing distributed applications
Software Engineering Journal
(1993)
P.D. Stotts
Expressing high-level visual concurrency structures in the PFG kernel language

There are more references available in the full text version of this article.

Cited by (4)

DSML4CP: A Domain-specific Modeling Language for Concurrent Programming
2015, Computer Languages, Systems and Structures
Citation Excerpt :
But, in this study, not only no language is offered for semantic control, but also, no tool is provided for using these models. Visual language of VISO [51] is designed for making concurrent programs, based on OCCAM language [52,53]. In this language, concurrent programs are designed in several abstract layers in modular form.
Nowadays, concurrent programs are an inevitable part of many software applications. They can increase the computation performance of the applications by parallelizing their computations. One of the approaches to realize the concurrency is using multi thread programming. However, these systems are structurally complex considering the control of the parallelism (such as thread synchronization and resource control) and also considering the interaction between their components. So, the design of these systems can be difficult and their implementation can be error-prone especially when the addressed system is big and complex. On the other hand, a Domain-specific Modeling Language (DSML) is one of the Model Driven Development (MDD) approaches which tackles this problem. Since DSMLs provide a higher abstraction level, they can lead to reduce the complexities of the concurrent programs. With increasing the abstraction level and generating the artifacts automatically, the performance of developing the software (both in design and implementation phases) is increased, and the efficiency is raised by reducing the probability of occurring errors. Thus, in this paper, a DSML is proposed for concurrent programs, called DSML4CP, to work in a higher level of abstraction than code level. To this end, the concepts of concurrent programs and their relationships are presented in a metamodel. The proposed metamodel provides a context for defining abstract syntax, and concrete syntax of the DSML4CP. This new language is supported by a graphical modeling tool which can visualize different instance models for domain problems. In order to clarify the expressions of the language; the static semantic controls are realized in the form of constraints. Finally, the architectural code generation is fulfilled via model transformation rules using the templates of the concurrent programs. To increase level of the DSML׳s leverage and to demonstrate the general support of concurrent programming by the DSML, the transformation mechanism of the tool supports two well-known and highly used programming languages for code generation; Java and C#. The performed experiments on two case studies indicate a high performance for proposed language. In this regard, the results show automatic generation of 79% of the final code and 86% of the functions/modules on average.
Formal semantics of visual occam
1998, Computer Languages
Visual programming languages (VPLs) have been proposed to simplify the task of programming and to make better use of human capabilities. Visual Occam (VISO) is a visual programming language for concurrent programming. It uses message passing for interprocess communication and processes are disjoint. The VISO language uses a modular approach to visual programming which simplifies the specification of programs. It has a graphical syntax based the language occam. The main emphasis in this paper is to provide formal semantics of VISO using process calculus. The semantics of all programming constructs and icons in VISO are given as well as a number of complete example programs and their translation in process calculus.
VPPE: A Novel Visual Parallel Programming Environment
2019, International Journal of Parallel Programming
Concurrent programming in VISO
2000, Concurrency Practice and Experience

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Visual Occam: Syntax and semantics

Abstract

I-pigs: an interactive graphical environment for concurrent programming

The Computer Journal

Graphical configuration programming

IEEE Computer

Structuring parallel and distributed programs

Software Engineering Journal

Durra, a structure description language for developing distributed applications

Software Engineering Journal

Expressing high-level visual concurrency structures in the PFG kernel language