A Denotational Semantics for Communicating Unstructured Code

An important property of programming language semantics is that they should be compositional. However, unstructured low-level code contains goto-like commands making it hard to define a semantics that is compositional. In this paper, we follow the ideas of Saabas and Uustalu to structure low-level code. This gives us the possibility to define a compositional denotational semantics based on least fixed points to allow for the use of inductive verification methods. We capture the semantics of communication using finite traces similar to the denotations of CSP. In addition, we examine properties of this semantics and give an example that demonstrates reasoning about communication and jumps. With this semantics, we lay the foundations for a proof calculus that captures both, the semantics of unstructured low-level code and communication.Comment: In Proceedings FESCA 2015, arXiv:1503.0437

Factoring Predicate Argument and Scope Semantics : underspecified Semantics with LTAG

In this paper we propose a compositional semantics for lexicalized tree-adjoining grammar (LTAG). Tree-local multicomponent derivations allow separation of the semantic contribution of a lexical item into one component contributing to the predicate argument structure and a second component contributing to scope semantics. Based on this idea a syntax-semantics interface is presented where the compositional semantics depends only on the derivation structure. It is shown that the derivation structure (and indirectly the locality of derivations) allows an appropriate amount of underspecification. This is illustrated by investigating underspecified representations for quantifier scope ambiguities and related phenomena such as adjunct scope and island constraints

Expression-Meaning and Vagueness

Brian Loar attempted to provide the Gricean program of intention-based semantics with an account of expression-meaning. But the theory he presented, like virtually every other foundational semantic or meta-semantical theory, was an idealization that ignored vagueness. What would happen if we tried to devise theories that accommodated the vagueness of vague expressions? I offer arguments based on well-known features of vagueness that, if sound, show that neither Brian’s nor any other extant theory could successfully make that adjustment, and this because, if sound, the arguments show not only that nothing can be the content of a vague expression, but also that no spoken language has a compositional semantics. This raises the question of what, really, are the facts about a language whose explanation might seem to require the language to have a compositional semantics, and whether there might not be a way to explain those facts on the assumption that the language doesn’t have a compositional semantics. In response to this question I offer a rough sketch of a view designed to suggest how what needs to be explained might be explained without appeal to compositional semantics

"Not not bad" is not "bad": A distributional account of negation

With the increasing empirical success of distributional models of compositional semantics, it is timely to consider the types of textual logic that such models are capable of capturing. In this paper, we address shortcomings in the ability of current models to capture logical operations such as negation. As a solution we propose a tripartite formulation for a continuous vector space representation of semantics and subsequently use this representation to develop a formal compositional notion of negation within such models.Comment: 9 pages, to appear in Proceedings of the 2013 Workshop on Continuous Vector Space Models and their Compositionalit

A process algebra for synchronous concurrent constraint programming

Concurrent constraint programming is classically based on asynchronous communication via a shared store. This paper presents new version of the ask and tell primitives which features synchronicity. Our approach is based on the idea of telling new information just in the case that a concurrently running process is asking for it. An operational and an algebraic semantics are defined. The algebraic semantics is proved to be sound and complete with respect to a compositional operational semantics which is also presented in the paper

From compositional to systematic semantics

We prove a theorem stating that any semantics can be encoded as a compositional semantics, which means that, essentially, the standard definition of compositionality is formally vacuous. We then show that when compositional semantics is required to be "systematic" (that is, the meaning function cannot be arbitrary, but must belong to some class), it is possible to distinguish between compositional and non-compositional semantics. As a result, we believe that the paper clarifies the concept of compositionality and opens a possibility of making systematic formal comparisons of different systems of grammars.Comment: 11 pp. Latex.

On Context Shifters and Compositionality in Natural Languages

My modest aim in this paper is to prove certain relations between some type of hyper-intensional operators, namely context shifting operators, and compositionality in natural languages. Various authors (e.g. von Fintel & Matthewson 2008; Stalnaker 2014) have argued that context-shifting operators are incompatible with compositionality. In fact, some of them understand Kaplan’s (1989) famous ban on context-shifting operators as a constraint on compositionality. Others, (e.g. Rabern 2013) take contextshifting operators to be compatible with compositionality but, unfortunately, do not provide a proof, or an argument in favor of their position. The aim of this paper is to do precisely that. Additionally, I provide a new proof that compositionality for propositional content (intension) is a proper generalization of compositionality for character (hyper-intensions)