Inference and Evolution of TypeScript Declaration Files

  • Erik Krogh Kristensen
  • Anders MøllerEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10202)


TypeScript is a typed extension of JavaScript that has become widely used. More than 2000 JavaScript libraries now have publicly available TypeScript declaration files, which allows the libraries to be used when programming TypeScript applications. Such declaration files are written manually, however, and they are often lagging behind the continuous development of the libraries, thereby hindering their usability. The existing tool tscheck is capable of detecting mismatches between the libraries and their declaration files, but it is less suitable when creating and evolving declaration files.

In this work we present the tools tsinfer and tsevolve that are designed to assist the construction of new TypeScript declaration files and support the co-evolution of the declaration files as the underlying JavaScript libraries evolve. Our experimental results involving major libraries demonstrate that tsinfer and tsevolve are superior to tscheck regarding these tasks and that the tools are sufficiently fast and precise for practical use.


Return Type Intentional Discrepancy Pull Request Type Declaration Spurious Change 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 647544).


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Aarhus UniversityAarhusDenmark

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