🚀 go-pugleaf

In her request, Maria Brielmann asks about a dialect of Z
to write concurrent specifications. I think she may be
referring to the Schumann-Pitt dialect of Z.

A number of following articles have mentioned the use of
CSP(-like) languages to complement a Z specification. Can
I suggest Matthew Hennessy's book, Algebraic theory of
processes, for the academic reader. It sets out the algebraic
theory of processes (surprisingly enough) where algebraic
structures, not entirely unlike Z, are described. This may
strengthen the idea that traces can be described in Z, as
Brendan Mahony suggested. 

For my own penny's worth, no-one seems to have highlighted
the different levels of abstraction between Z and CSP(-like
languages). Z is about 'whats' and CSP is (mostly?) about
'hows' and there is a difference. I think Jim Davies hinted
this when he said "...using CSP to specify the patterns of
communication between system components, and then Z to specify
the computational aspects of the components themselves",
although personally I'd do it the other way around.

Julian