Formal language

About: Formal language is a research topic. Over the lifetime, 5763 publications have been published within this topic receiving 154114 citations.

Current trends in theoretical computer science: entering the 21st centuary

Abstract: Computational Complexity (E Allender et al.) Formal Specification (H Ehrig et al.) Login in Computer Science (Y Gurevich et al.) Concurrency (M Nielsen et al.) Natural Computing (G Rozenberg et al.) Formal Language Theory (A Salomaa et al.)

Tool specification with GTSL

Abstract: The definition of software development methods encompasses the definition of syntax and static semantics of formal languages. These languages determine documents to be produced during the application of a method. Developers demand language-based tools that provide document production support, check the syntax and static semantics of documents, and thus implement methods. Method integration must determine inter-document consistency constraints between documents produced in the various tasks. Tools must, therefore, be integrated to implement the required method integration and check or even preserve inter-document consistency. The focus of this paper is on the specification of such integrated tools and outlines the main concepts of the object-oriented tool specification language GTSL (GOODSTEP Tool Specification Language). GOODSTEP is an ESPRIT-III project (no. 6115) to produce a General Object-Oriented Database for SofTware Engineering Processes.

A Generalisation of Parikh's Theorem in Formal Language Theory

Abstract: We show that when a family of languages F has a few appropriate closure-properties, all languages algebraic over F are still equivalent to languages in F when occurrences of symbols are permuted At the same time, the methods used imply a new and simple algebraic proof of Parikh’s original theorem, directly transforming an arbitrary context-free grammar into a letter-equivalent regular grammar Further applications are discussed

Characterization of co-observable languages and formulas for their super/sublanguages

Abstract: We present fixed-point based characterization of several classes of co-observable languages that are of interest in the context of decentralized supervisory control of discrete-event systems, including C&P /spl or/ D&A co-observable languages, C&P co-observable languages, and D&A co-observable languages. We also provide formulas for computing super/sublanguages for each of these classes. In cases where the class of co-observable languages is not closed under intersection/union, we provide upper/lower bound of the super/sublanguage formula we present. The computation of super/sublanguages and also computation of their upper/lower bounds has lead to the introduction of other classes of co-observable languages, namely, strongly C&P co-observable languages, strongly D&A co-observable languages, locally observable languages, and strongly locally observable languages. Fixed-point based characterization of all the above language classes is also given, and their closure under intersection/union is investigated. We also study whether the fixed-point operator preserves prefix closure, relative closure (also called L/sub m/(G)-closure), and controllability.

Supporting Formal Verification of Crosscutting Concerns

Abstract: This paper presents an approach to formal verification of the properties of systems composed of multiple crosscutting concerns. The approach models concerns as sets of concurrent processes, and provides a method of composition that mimics the composition operators of existing multiple-concern implementation languages. A case study demonstrates the composition process and shows how formal verification of different composition strategies can detect potential problems. We also discuss the need for a general model of concerns that can be handled by different formal languages.