Ada 2012 brings various enhancements to the Ada language, says a spokesperson. Related to contract-based programming, Ada 2012 adds the ability to specify preconditions and postconditions for subprograms and invariants for private (encapsulated) types, which take the form of Boolean expressions that can be interpreted (under programmer control) as run-time conditions to be checked.
These contract-based programming features fit with Ada’s Object-Oriented Programming model, and support the type substitutability guidance supplied in DO-332, Object-Oriented Technologies and Related Techniques Supplement to the DO-178C/ED-12C avionics software safety standard.
The language revision, known as Ada 2012, was under the auspices of ISO/IEC JTC1/SC22/WG9 and was conducted by the Ada Rapporteur Group (ARG) subunit of WG9, with sponsorship in part from the Ada Resource Association (ARA) and Ada-Europe.
“Ada 2012 is a significant technical accomplishment,” says Dr. Joyce Tokar, convenor of WG9.
The formal approval of the standard was issued on November 20 by ISO/IEC JTC 1, and the standard was published on December 15.
“Ada 2012 is a major advance in the state of the art in programming languages,” says Dr. Edmond Schonberg, rapporteur of the ARG. “The new features answer real user needs, and help cement Ada’s reputation as a language of choice for systems where reliability, safety, and security are paramount.”