Thesis Proposal: Object Propositions
نویسنده
چکیده
predicates can be used to express properties of elds using integers, but reasoning about integers is di cult. We are going to employ a theorem prover to prove properties about integers. Most probably, we are going to use the Z3 theorem prover [3]. Kevin Bierho has implemented a tool called JavaSyp [1] that uses the SMT solver Z3 to formally verify Java code. We initially wanted to modify JavaSyp in order to implement Oprop, but that proved to be a di cult task. There are many details that are di erent between JavaSyp and what Oprop needs to do: JavaSyp uses borrowing and capture/release because the tool does not implement fractional permissions. Oprop does not use borrowing, but instead it uses fractional permissions. Fractions give more precision than the borrowing mechanism and we are going to implement fractional permissions. Oprop will implement the pack/unpack mechanism, while JavaSyp does not implement this mechanism. JavaSyp implements instead exposure blocks" that show how elds should be accessed. These features are closely related: when the elds of an object are unpacked (when the object proposition that encapsulated them is unpacked), we can think of them as being exposed". In Bierho 's system, there are unique" and immutable" exposure blocks. Fields can be assigned inside unique exposure blocks, with eld reads yielding the eld's original permission. Inside an immutable block, reading elds results in a weakened eld permission. The technical di erence is that in my system I do not have immutable permissions, but instead one can always write to the elds of an object (in some cases, one has to make sure that the invariant is preserved). I acknowledge that this is just an incidental di erence and the ideas of pack/unpack vs. exposure blocks are very similar. JavaSyp has class invariants, but Oprop will not have them and instead it will have invariants for objects that are shared. Our plan is to create a tool similar to JavaSyp that rst translates the code and speci cations into an intermediary language (such as those used by Dafny or Chalice, from the RiSE group at Microsoft Research [7]) and then use that intermediary tool together with Z3 to obtain the nal result. 9 Validation and Evaluation We will evaluate the usefulness of the Oprop tool and of the object proposition methodology by designing a user study where we observe how the Oprop plugin improves the e ciency of programmers. We will also try to solve the open problem Finalizers, that will be described below, using our methodology. We have already made some contributions to the speci cation and veri cation of the Composite pattern, and we will nalize the veri cation of the Composite pattern.
منابع مشابه
The Tractatus on Logical Consequence*
THE TRACTATUS ON LOGICAL CONSEQUENCE José L. Zalabardo ABSTRACT: I discuss the account of logical consequence advanced in Wittgenstein’s Tractatus. I argue that the role that elementary propositions are meant to play in this account can be used to explain two remarkable features that Wittgenstein ascribes to them: that they are logically independent from one another and that their components re...
متن کاملA native proposal for the philosophy of history
Though philosophy of history like other fields of knowledge has its roots in eastern traditional knowledge, as an epistemological branch it appeared in West and then entered in East. Present states of knowledge in Islamic Iran, particularly with regard to the necessities and grounds of change in humanities, have prepared an opportunity to present a proposal in the field of philosophy of history...
متن کاملPropositions and the Metaphysics of Time
The central point of Brogaard's interesting essay is that temporalism, roughly, the thesis that there are propositions whose evaluation is sensitive to time (14), is a better alternative to standard semantic eter-nalism, roughly, the thesis that no proposition is sensitive to temporal variation. Five theoretical roles individuate propositions: (i) semantic values of sentences, (ii) objects of a...
متن کاملA Puzzle about Truth and Singular Propositions 1 1 . Singular Propositions
My dissertation consists of three essays in the Metaphysics of Modality: In "A Puzzle about Truth and Singular Propositions," I consider two theses that seem to be true and then an argument for the conclusion that they form an inconsistent pair. One thesis is that a proposition that is singular with respect to a given object implies that the object exists. This is so because the proposition pre...
متن کاملThesis Proposal: Type Theory for Mobility and Locality
In this thesis, we consider distributed programming from a type-theoretic, logical perspective. We develop a calculus for distributed programming based on a constructive modal logic. Through a Curry-Howard interpretation of proof terms as programs and propositions as types, we show that logical necessity is connected to mobility, and possibility to remote locality. We give an operational interp...
متن کامل