ANN: SPARK Book - Sample Chapters now free on-line

ANN: SPARK Book - Sample Chapters now free on-line

[Rod Chapman]

I'm pleased to announce the availability of the "Sample Chapters" of the
forthcoming new book "High Integrity Software: The SPARK Approach to
Safety and Security" by John Barnes.

 The sample chapters are freely available in PDF format on www.sparkada.com

 The book is now at the printers.  We expect a UK
publication date of 21st March.  Availability is
expected in the USA approximately 4 weeks later.

 The book can be pre-ordered now at various book-sellers including
www.amazon.com and www.amazon.co.uk.

 All the best,
  Rod Chapman, SPARK Team, Praxis Critical Systems Limited

Re: ANN: SPARK Book - Sample Chapters now free on-line

[Volkert]

"Neil Groves" <neilgroves_no_spam@dial.pipex.com> wrote in message news:<vaqcvcruvo1493@corp.supernews.com>...
> I thought that SPARK required contra-variance which is fundamentally
> incompatible with the covariance in Eiffel?
There is no concept of contra-/co-variance in Spark. 
As i understand Spark, the redefinition of a procedure (method) 
in a child of a tagged type (class) must have >>exactly<< the 
same procdure signature as given with the parent type. A very 
strong conformance rule, but remember: Spark has NO references (entities) 
and NO dispatching (class wide types with offers you dynamic binding)

Volkert