Prover Studio 2 with HLL support has been released! Prover Studio was launched (https://www.prover.com/product-news/introducing-prover-studio/) as an integrated development environment for Prover Trident. Prover Studio now joins our family of tools that support HLL. With the new version, you will be able to read, write, and navigate HLL and sHLL models and safety properties. Prover [...]
Beginning May 18th, I led a four-day online crash course on HLL for a dozen Safety Engineers. Due to the French COVID-19 lockdown, the course was conducted via Microsoft Teams, alternating lectures and exercises. An online course is a very special experience: you can get very close to a student’s activities when sharing terminals and [...]
On November 21st, we met at the office of Ikos Consulting in Levallois-Perret. In the presence of the creators, the designers, and the users of the language, we agreed about future enhancement processes and started the process to precisely define the next version of the HLL language definition. The next steps will be to concretely [...]
In a recent post we celebrated the 10th anniversary of the declarative, formal language HLL. The language is used extensively in the railway signaling domain for the formal verification of interlocking logic and CBTC subsystems (such as zone controllers). In this more technical post we will familiarize the reader further with HLL, by formalizing the famous [...]
The Tool providers that support HLL have now agreed on the content of the next published version of HLL. It will be a merge of the different dialects of HLL that exist today. One language for all Over the years tool providers have developed HLL in different directions in order to solve their particular needs and to [...]
The HLL Forum meeting we had in December decided to let a subgroup work on a new language definition meeting emerging needs in the market. Some of us in this subgroup compete as software tool providers, however we share the vision of a standard language definition, and we strongly believe that the users of HLL [...]
On Dec 4, the first HLL forum organized by Prover was held in Paris. The event brought together the major users of the HLL language. The forum was an exciting opportunity to learn how HLL is used today, and to discuss how HLL can evolve in a controlled way to meet the challenges of tomorrow. [...]
The formal language HLL (High Level Language) has emerged in recent years as a quite popular language for formal verification of safety-critical systems, especially in the railway signaling domain. This year marks the 10th anniversary of its conception. The history of HLL The language has its roots in the proof engine technologies developed by Prover in the 1980s (Stålmarck's [...]
