Lists of Opportunities: My Experience as a School Librarian During the COVID-19 Pandemic

In this paper I share my experiences, opinions and perspectives of running a school library during the COVID-19 pandemic. I discuss the difficulties and problems I have encountered, but also the opportunities for creativity that have presented themselves. From experiencing government cutbacks to layoffs and school closures, I discuss my feelings and frustrations about COVID-19 and how it prevented me from doing my job. I demonstrate how the pandemic heightened the feeling of isolation and loneliness in a job that can already make one feel disconnected; I highlight the importance and need for human connection. I also examine the new creative opportunities that working during a pandemic has given me, like asynchronous programming, collection development, professional development and a chance to experiment or renovate. This paper is meant to highlight the importance of school libraries and start a discussion of our role before and after the pandemic. Advocacy helps ensure that school libraries remain open. My goal is to give a glimpse of day-to-day library practice in a school library during the pandemic and share ideas and information with the library and information community. My views and opinions are my own, and the context will be different in every school.

General Decidability Results for Asynchronous Shared-Memory Programs: Higher-Order and Beyond

The model of asynchronous programming arises in many contexts, from low-level systems software to high-level web programming. We take a language-theoretic perspective and show general decidability and undecidability results for asynchronous programs that capture all known results as well as show decidability of new and important classes. As a main consequence, we show decidability of safety, termination and boundedness verification for higher-order asynchronous programs—such as OCaml programs using Lwt—and undecidability of liveness verification already for order-2 asynchronous programs. We show that under mild assumptions, surprisingly, safety and termination verification of asynchronous programs with handlers from a language class are decidable iff emptiness is decidable for the underlying language class. Moreover, we show that configuration reachability and liveness (fair termination) verification are equivalent, and decidability of these problems implies decidability of the well-known “equal-letters” problem on languages. Our results close the decidability frontier for asynchronous programs.

JAVASCRIPT ASYNCHRONOUS PROGRAMMING

JavaScript has become more and more popular in recent years because its wealthy features as being dynamic, interpreted and object-oriented with first-class functions. Furthermore, JavaScript is designed with event-driven and I/O non-blocking model that boosts the performance of overall application especially in the case of Node.js. To take advantage of these characteristics, many design patterns that implement asynchronous programming for JavaScript were proposed. However, choosing a right pattern and implementing a good asynchronous source code is a challenge and thus easily lead into less robust application and low quality source code. Extended from our previous works on exception handling code smells in JavaScript and exception handling code smells in JavaScript asynchronous programming with promise, this research aims at studying the impact of three JavaScript asynchronous programming patterns on quality of source code and application.