So you could sayvar var = new Varchar();-) -------- Ursprüngliche Nachricht --------Von: Jesper Steen Møller <jes...@selskabet.org> Datum: 08.03.18 07:50 (GMT+01:00) An: dev@groovy.apache.org Betreff: Re: About supporting `var` of Java10+ Hi list
It’s not a keyword in Java 10, it’s just a reserved identifier. In other words, “int var = 10;” is still legal. I’m thinking we should remain as conservative as Java in those matters. -Jesper > On 8 Mar 2018, at 02.23, MG <mg...@arscreat.com> wrote: > > Hi Daniel, > > I agree that it does not make much sense to closely mirror the details of the > Java specifications in Groovy, but I still think that simply treating var the > same as def looses some potential for the static compilation case, e.g.: > var myVar = new Foo() > myVar = 123 // Allowed when var === def, forbidden if myVar has type Foo > > For different reasons (scenarios where reflection on classes is used, such as > in my library), the same goes for > final myField = new Foo() // myField should have type Foo > > As http://openjdk.java.net/jeps/286 correctly mentions, type inference is > not magic, but in my mind this comes down to a 90+% solution again, namely > that covering the two cases: > 1) var myVar = new Foo() // myVar is of type Foo > 2) var myVar = myMethod() // myVar is of return type of myMethod > will cover a lot of ground, and I therefore believe it would be ok to fall > back to var/final === def in all other cases for now. If someone wants to / > has time, he can improve on this later. > > My 8.05762816 Cent, > mg > > >> On 08.03.2018 00:53, Daniel Sun wrote: >> Hi all, >> >> As GROOVY-8498[1] describes as follows, in order to compatibility with >> Java 10+, Groovy should support `var` the reserved type name. The reference >> implementation has been pushed to master and 2.6.0 branch, you can find it >> via the link[2]. >> >> Any thoughts? >> >> *GROOVY-8498:* >> ``` >> This is to provide compatibility with: >> http://openjdk.java.net/jeps/286 (Java 10) >> http://openjdk.java.net/jeps/323 (targeted for Java 11) >> >> Java 10 provides var to allow reduced ceremony by avoiding manifest >> declaration of types for local variables for cases where type inferencing >> can be supported. Groovy already does this with "def" and has it's own >> approach for type inferencing within type-checked/compile static code. With >> this in mind, it seems to make most sense for Groovy to have "var" as an >> alias for "def" rather than closely mimic only the use cases allowed by >> Java. >> ``` >> >> Cheers, >> Daniel.Sun >> >> [1] https://issues.apache.org/jira/browse/GROOVY-8498 >> [2] >> https://github.com/apache/groovy/commit/f30741f519f4012c7cca3959ade9e4ec12625e45 >> >> >> >> -- >> Sent from: http://groovy.329449.n5.nabble.com/Groovy-Dev-f372993.html >> >
