CSL4P: A Contract Specification Language for Platforms

Abstract

The contract‐based design formalism supports compositional design and verification, and generalizes many other languages where components are defined in terms of their assumptions and guarantees. Most languages and tools for contract‐based design provide constructs to define, instantiate, and connect contracts, but fall short in capturing families of potential architectures in a flexible way. This article presents a Contract‐Based Specification Language for Platforms (CSL4P). A platform comprises a set of contract types and a set of constraints called rules. Contract types can be instantiated and connected to form platform instances. While the meaning of composition is predefined in most languages, composition rules are used in CSL4P to provide a finer control on the semantics of interconnections. In addition, the separation of contract types from rules allows users of CSL4P to define different platforms out of the same set of components. This article describes syntax and semantics of the language, a development environment, which includes a compiler and a verification back‐end, and an application example.

Structural Contracts -- Contracts for Type Construction & Dependent Types to Ensure Consistency of Extra-Functional Reasoning

“…As we first identified the difficulties with properly defining, composing and refining EFPs in terms of contracts, we outlined a problem sketch in [2] and suggested an early approach, based on extending the refining set M * by another subcomponent, having assumptions and guarantees about the interconnection relations between the other components' variables. Most closely related, [4] agrees with our idea, but by distinguishing different contract types and specifying assertion and validity rules (i. e. functions and predicates) between the variables of that contract types. In contrast to SCs, these rules and types are defined as sets at the level of platforms, limiting the set of correctly refineable property specifications according to only those rules and types of that platform.…”

Methodologies for the Synthesis of Reliable MEA Electrical Power System Architectures

“…Following this line, applications for MEA EPS have been reported in [9], [11] with some testbeds developed on TULIP [12]- [14] which has been implemented in CAD with the JTLV verification scripting environment [15]. Further plans to investigate automatic generation of contracts and contract language definition [5] are expected [16]. CbD presents a rigorous methodology for the design of MEA EPS consisting in three main stages: 1) topology synthesis, 2) control synthesis, and 3) simulation-based design exploration and verification.…”