1 research outputs found
Side Effects in Steering Fragments
In this thesis I will give a formal definition of side effects. I will do so
by modifying a system for modelling program instructions and program states,
Quantified Dynamic Logic, to a system called DLAf (for Dynamic Logic with
Assignments as Formulas), which in contrast to QDL allows assignments in
formulas and makes use of short-circuit evaluation. I will show the underlying
logic in those formulas to be a variant of short-circuit logic called
repetition-proof short-circuit logic.
Using DLAf I will define the actual and the expected evaluation of a single
instruction. The side effects are then defined to be the difference between the
two. I will give rules for composing those side effects in single instructions,
thus scaling up our definition of side effects to a definition of side effects
in deterministic \dlaf-programs. Using this definition I will give a
classification of side effects, introducing as most important class that of
marginal side effects. Finally, I will show how to use our system for
calculating the side effects in a real system such as Program Algebra (PGA).Comment: Master's thesis - Master of Logic - University of Amsterda