Enhancing semantic bidirectionalization via shape bidirectionalizer plug-ins

Abstract

Abstract Matsuda et al . (Matsuda, K., Hu, Z., Nakano, K., Hamana, M. & Takeichi, M. (2007) Bidirectionalization transformation based on automatic derivation of view complement functions. In Proceedings of the International Conference on Functional Programming . ACM Press, pp. 47–58) and Voigtländer (Voigtländer, J. (2009) Bidirectionalization for free! In Proceedings of Principles of Programming Languages . ACM Press, pp. 165–176) have introduced two techniques that given a source-to-view function provide an update propagation function mapping an original source and an updated view back to an updated source, subject to standard consistency conditions. Previously, we developed a synthesis of the two techniques, based on a separation of shape and content aspects (Voigtländer, J., Hu, Z., Matsuda, K. & Wang, M. (2010) Combining syntactic and semantic bidirectionalization. In Proceedings of the International Conference on Functional Programming . ACM Press, pp. 181–192). Here we carry that idea further, reworking the technique of Voigtländer such that any shape bidirectionalizer (based on the work of Matsuda et al . (2007) or not) can be used as a plug-in, to good effect. We also provide a data-type-generic account, enabling wider reuse, including the use of pluggable bidirectionalization itself as a plug-in.