A Symmetric Approach to Compilation and Decompilation

Just as specializing a source interpreter can achieve compilation from a source language to a target language, we observe that specializing a target interpreter can achieve compilation from the target language to the source language. In both cases, the key issue is the choice of whether to perform an evaluation or to emit code that represents this evaluation. We substantiate this observation by specializing two source interpreters and two target interpreters. We first consider a source language of arithmetic expressions and a target language for a stack machine, and then the lambda-calculus and the SECD-machine language. In each case, we prove that the target-to-source compiler is a left inverse of the source-to-target compiler, i.e., it is a decompiler. In the context of partial evaluation, compilation by source-interpreter specialization is classically referred to as a Futamura projection. By symmetry, it seems logical to refer to decompilation by target-interpreter specialization as a Futamura embedding

Temperature-Induced Wavelength Shift of Electron-Beam-Pumped Lasers from CdSe, CdS, and ZnO

Experimental results on the temperature dependence of the laser frequency and threshold pump power are presented in the range from liquid helium to room temperature for electron-beam-pumped CdSe, CdS, and ZnO lasers. A linear shift of the laser frequency at high temperatures and a relatively slow linear increase of threshold with increasing temperature are found. A model is proposed that takes into account the reabsorption in the crystal below the lowest exciton energy. The results of this model are in quantitative agreement with the experimental data. The absorption coefficient at the laser frequency is determined in the three materials

Axioms for Recursion in Call-by-Value

We propose an axiomatization of fixpoint operators in typed call-by-value programming languages, and give its justifications in two ways. First, it is shown to be sound and complete for the notion of uniform T-fixpoint operators of Simpson and Plotkin. Second, the axioms precisely account for Filinski's fixpoint operator derived from an iterator (infinite loop constructor) in the presence of firstclass continuations, provided that we define the uniformity principle on such an iterator via a notion of effect-freeness (centrality). We then explain how these two results are related in terms of the underlying categorical structures

Inter-industry wage differentials: What do we know?

Substantial wage differentials are observed in all countries between workers employed in different sectors. How can we explain these wage differentials? Do they entirely derive from the sectoral diversity in personal productive characteristics and task descriptions or do employer features also play a role? Are inter-industry wage differentials smaller in countries with centralised and coordinated collective bargaining? Are they shaped by international trade and product market regulations? What is their impact on gender and other types of inequality? Do they affect economic performance? These are the main questions that we address in this review of the literature.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Varieties of effects

Abstract. We introduce the notion of effectoid as a way of axiomatising the notion of “computational effect”. Guided by classical algebra, we define several effectoids equationally and explore their relationship with each other. We demonstrate their computational relevance by applying them to global exceptions, partiality, continuations, and global state.