Concrete Data Structure
(CDS) A model of programming language terms developed in the context of constructing fully abstract semantics for sequential languages. A CDS is a 4-tuple (C,V,E,|-) where C is a cell, V is a value, E is an event and |- is an "enabling relation". An event is a cell and a value. A cell C is "enabled" by a set of events S if S |- C. A state is a set of events which are consistent in that the values they give for any cell are all equal. Every cell in a state is enabled.