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+# [2.0.0](https://github.com/RedPRL/yuujinchou/compare/1.0.0...2.0.0) (2022-03-07)
+
+
+### Bug Fixes
+
+* **action:** pass rev_prefix to the final union ([#58](https://github.com/RedPRL/yuujinchou/issues/58)) ([000df38](https://github.com/RedPRL/yuujinchou/commit/000df384e4cb75773ed25b185f7c2a3f86acfdaa))
+
+
+### Code Refactoring
+
+* **trie:** drop almost all requirements of physical equality ([#54](https://github.com/RedPRL/yuujinchou/issues/54)) ([262e1be](https://github.com/RedPRL/yuujinchou/commit/262e1be09fed1005e5ddf87cc9f3d7de6810d79c))
+
+
+### Features
+
+* **action:** monadic union ([#57](https://github.com/RedPRL/yuujinchou/issues/57)) ([6a95ace](https://github.com/RedPRL/yuujinchou/commit/6a95aceed8469cd55a380edd70ebaa2fe5e143ca))
+* **trie:** monadic updates with Stdlib.result ([#55](https://github.com/RedPRL/yuujinchou/issues/55)) ([b2e783b](https://github.com/RedPRL/yuujinchou/commit/b2e783ba465865e0479a99ba9430e29b3956cc0d))
+
+
+### BREAKING CHANGES
+
+* **action:** run and run_with_hooks now take a monadic merger
+* **trie:** drop all *_endo functions and physical equality requirements