Following the announcement of JEP 394 [1] the latest version of the spec is now available at:
http://cr.openjdk.java.net/~gbierman/jep394/latest/ I have fixed the bugs spotted by Brian in the previous draft. I have also tidied up the treatment of annotations (See sections 9.6.4.1 and 9.7.4 along with the refactored grammar for type test patterns 14.20.1.1) Still time to pass on comments! Gavin [2] https://openjdk.java.net/jeps/394 > On 5 Oct 2020, at 13:53, Gavin Bierman <gavin.bier...@oracle.com> wrote: > > Dear all: > > A draft of the spec for the Patterns in instanceof feature that we plan to > finalize in JDK 16 is now available: > > http://cr.openjdk.java.net/~gbierman/8250623/latest/ > > [NB: The URL will change once we have a JEP number, and will be announced.] > > The changes are the same as those in the second preview that was released in > Java SE 16, except for minor editorial changes and the following: > > - To lift the restriction that pattern variables are implicitly final. This > allows pattern variables to be considered as a strict subset of local > variables. A number of simplifications to the spec result from this change. > > - To make it a compile-time error for an expression of type _S_ to be matched > against a pattern of type _T_, where _S_ is a subtype of _T_. (This pattern > match will always succeed and is then pointless. The opposite case, where a > pattern match will always fail is already a compile-time error.) > > Comments welcome! > > Gavin
