%0 Journal Article
%T An Instruction Sequence Semigroup with Involutive Anti-Automorphisms
%A J.A. Bergstra
%A A. Ponse
%J Scientific Annals of Computer Science
%D 2009
%I Alexandru Ioan Cuza University of Iasi
%X We introduce an algebra of instruction sequences by presenting asemigroup C in which programs can be represented without directionalbias: in terms of the next instruction to be executed, C has both forwardand backward instructions and a C-expression can be interpretedstarting from any instruction. We provide equations for thread extraction,i.e., C¡¯s program semantics. Then we consider thread extractioncompatible (anti-)homomorphisms and (anti-)automorphisms. Finallywe discuss some expressiveness results.
%U http://www.info.uaic.ro/bin/download/Annals/XIX/XIX_2.pdf