On Mon, 9 May 2022 14:37:35 GMT, Jan Lahoda <jlah...@openjdk.org> wrote:
>> 8262889: Compiler implementation for Record Patterns >> >> A first version of a patch that introduces record patterns into javac as a >> preview feature. For the specification, please see: >> http://cr.openjdk.java.net/~gbierman/jep427+405/jep427+405-20220426/specs/patterns-switch-record-patterns-jls.html >> >> There are two notable tricky parts: >> -in the parser, it was necessary to improve the `analyzePattern` method to >> handle nested/record patterns, while still keeping error recovery reasonable >> -in the `TransPatterns`, the desugaring of the record patterns is very >> straightforward - effectivelly the record patterns are desugared into >> guards/conditions. This will likely be improved in some future >> version/preview >> >> `MatchException` has been extended to cover additional cases related to >> record patterns. > > Jan Lahoda has updated the pull request with a new target base due to a merge > or a rebase. The pull request now contains eight commits: > > - Merge branch 'type-pattern-third' into patterns-record-deconstruction3 > - Using Type.isRaw instead of checking the AST structure. > - Exhaustiveness should accept supertypes of the specified type. > - Renaming the features from deconstruction pattern to record pattern. > - Fixing guards after record patterns. > - Raw types are not allowed in record patterns. > - Reflecting review feedback. > - 8262889: Compiler implementation for Record Patterns I've noticed that this code: class Test { String e(E e) { return switch (e) { case A -> "42"; }; } enum E { A, B; } } fails with: Test.java:3: error: the switch expression does not cover all possible input values return switch (e) { ^ 1 error before this change but gets accepted with no error message after it ------------- PR: https://git.openjdk.java.net/jdk/pull/8516