Investigation of Reason as a substitute for JavaScript

Abstract: JavaScript has in recent years become one of the most utilized programming languages for developing different kinds of applications. However, even though it has received a lot of praise for its simplicity, versatility and highly active community, it lacks some functionalities and features that a lot of programmers highly value, like static and strict typing, compile-time debugging, and to not be required to make use of third-party libraries to integrate crucial functionality. However, several new languages built on top of JavaScript have been developed to address and resolve these issues developers find with JavaScript without losing the benefits that come with it. One of these super- set languages is Reason, the new syntax and toolchain powered by the OCaml compiler. This thesis aims to address whether there are scenarios where Reason could act as a reasonable substitute of JavaScript by investigating how the languages compare in regards to different criteria. The criteria examined are writability, data structures and typing, reliability and testing, community support, market demand, portability, and performance. The findings show that using Reason over JavaScript could result in higher reliability and robustness due to static type checking, compile-time debugging, and other usable feature like pattern matching and explicitly defined custom data structures, which is convenient when dealing with advanced data. On the other hand, Reason’s interoperability with JavaScript is something that is not very straight-forward and makes it difficult to integrate Reason into an existing JavaScript codebase or include one of the thousand of JavaScript- written dependencies available on npm. Furthermore, with Reason being a rather young language yet to be used by a larger audience, both the community support and market demand are a lot smaller than that of JavaScript and have yet to see a significant growth, which leads to questions about the overall survival of the language. Both of the languages have a significant role and contribute with different kind of functionality. However, with the non-straightforward interoperability, Reason loses a lot of potential benefits to be gained from JavaScript, which could be problematic in the long run and could impact the future of Reason.