Re: RFR: 8262889: Compiler implementation for Record Patterns [v4]
On Mon, 9 May 2022 20:52:15 GMT, Vicente Romero wrote:
> 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 errors after the change in this
> PR
Oops, sorry, should be fixed now
([a0d0c78](https://github.com/openjdk/jdk/pull/8516/commits/a0d0c78bcbb5ecb010c2e9bd235b3ae89eb00823)).
-
PR: https://git.openjdk.java.net/jdk/pull/8516
Re: RFR: 8262889: Compiler implementation for Record Patterns [v4]
On Mon, 9 May 2022 14:37:35 GMT, Jan Lahoda 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
Re: RFR: 8262889: Compiler implementation for Record Patterns [v4]
On Mon, 9 May 2022 14:37:35 GMT, Jan Lahoda 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 src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Flow.java line 822: > 820: > nestedComponentPatterns); > 821: > 822: //for each of the symbols covered by the starting component, > find all deconstruction patterns this comment should probably read: find all `record` patterns? - PR: https://git.openjdk.java.net/jdk/pull/8516
Re: RFR: 8262889: Compiler implementation for Record Patterns [v4]
On Fri, 6 May 2022 17:40:25 GMT, Jan Lahoda wrote: >> src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java line 4217: >> >>> 4215: } >>> 4216: ListBuffer outBindings = new ListBuffer<>(); >>> 4217: List recordTypes = expectedRecordTypes; >> >> nit: probably a matter of style but why not reusing the already declared >> `expectedRecordTypes` declaring a new variable seems unnecessary > > Please note the full `expectedRecordTypes` are used for error reporting, but > the reference to `List` in `recordTypes` is overwritten in the loop (at the > time of an error report, it may not longer point to the full expected types, > and hence cannot be used for error reporting). Ok I see, thanks - PR: https://git.openjdk.java.net/jdk/pull/8516
Re: RFR: 8262889: Compiler implementation for Record Patterns [v4]
> 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 - Changes: https://git.openjdk.java.net/jdk/pull/8516/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8516&range=03 Stats: 2255 lines in 50 files changed: 2169 ins; 15 del; 71 mod Patch: https://git.openjdk.java.net/jdk/pull/8516.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/8516/head:pull/8516 PR: https://git.openjdk.java.net/jdk/pull/8516
