Local Variable Type Inference - prototype

[Maurizio Cimadamore]

Thanks - pushed

Maurizio

On 11/03/16 08:01, Robert Field wrote:
> Patch to fix this attached.
>
> Apply as desired.
>
> -Robert
>
>
> On 03/10/16 15:41, Maurizio Cimadamore wrote:
>>
>>
>> On 10/03/16 22:55, Robert Field wrote:
>>>
>>> On 03/10/16 14:21, Remi Forax wrote:
>>>> At least, jshell need some tweaks :)
>>>
>>> Yes, it will.  Thanks Remi!
>>>
>>> It will need the analysis pass of the compiler run so that the type 
>>> can be determined.  Variables are implemented as fields.
>>>
>>> Is this something I should work on now?
>> One question for you Robert: currently javac does not parse 'var' as 
>> a special Token - as doing that requires even more jshell changes; 
>> I'm happy to leave the code as is, but if, when hacking on the jshell 
>> side, you discover that a VAR token would be useful please let me know.
>>
>> Maurizio
>>>
>>> -Robert
>>>
>>>>
>>>> $ /usr/jdk/jdk-9/bin/java 
>>>> -Xbootclasspath/p:langtools/dist/lib/jdk.compiler.jar:langtools/dist/lib/jdk.jshell.jar:langtools/dist/lib/jdk.internal.le.jar:langtools/dist/lib/jdk.jdi.jar 
>>>> jdk.internal.jshell.tool.JShellTool
>>>> |  Welcome to JShell -- Version 9-internal
>>>> |  Type /help for help
>>>>
>>>> -> void m() {
>>>>>> var a = 3;
>>>>>> }
>>>> |  Added method m()
>>>>
>>>> -> m()
>>>>
>>>> -> var a = 3;
>>>> Exception in thread "main" 
>>>> java.lang.StringIndexOutOfBoundsException: begin -1, end -1, length 10
>>>>     at java.lang.String.checkBoundsBeginEnd(String.java:3122)
>>>>     at java.lang.String.substring(String.java:1910)
>>>>     at jdk.jshell.Wrap$Range.part(Wrap.java:168)
>>>>     at jdk.jshell.Wrap$RangeWrap.<init>(Wrap.java:350)
>>>>     at jdk.jshell.Wrap.varWrap(Wrap.java:97)
>>>>     at jdk.jshell.Eval.processVariables(Eval.java:227)
>>>>     at jdk.jshell.Eval.eval(Eval.java:116)
>>>>     at jdk.jshell.JShell.eval(JShell.java:355)
>>>>     at 
>>>> jdk.internal.jshell.tool.JShellTool.processCompleteSource(JShellTool.java:1923)
>>>>     at 
>>>> jdk.internal.jshell.tool.JShellTool.processSource(JShellTool.java:1911) 
>>>>
>>>>     at 
>>>> jdk.internal.jshell.tool.JShellTool.processSourceCatchingReset(JShellTool.java:652)
>>>>     at jdk.internal.jshell.tool.JShellTool.run(JShellTool.java:632)
>>>>     at jdk.internal.jshell.tool.JShellTool.start(JShellTool.java:427)
>>>>     at jdk.internal.jshell.tool.JShellTool.start(JShellTool.java:400)
>>>>     at jdk.internal.jshell.tool.JShellTool.main(JShellTool.java:390)
>>>>
>>>> Rémi
>>>>
>>>> ----- Mail original -----
>>>>> De: "Maurizio Cimadamore" <maurizio.cimadamore at oracle.com>
>>>>> À: platform-jep-discuss at openjdk.java.net
>>>>> Envoyé: Jeudi 10 Mars 2016 15:48:25
>>>>> Objet: Local Variable Type Inference - prototype
>>>>>
>>>>> Hi,
>>>>> I've pushed the first iteration of the local variable type inference
>>>>> prototype in the sandbox repository[1]. For those willing and brave
>>>>> enough to experiment, the branch name is "JEP-286-branch". We are 
>>>>> also
>>>>> working to get some ready-made binary snapshots out of the door 
>>>>> and hope
>>>>> to have an update on that soon.
>>>>>
>>>>> This first iteration supports the 'var-only' syntax style:
>>>>>
>>>>> var s = "Hello!";
>>>>>
>>>>> That is, the type of 's' is inferred from the initializer, and no
>>>>> special assumption is made about mutability.
>>>>>
>>>>> Please share your experience with the prototype. For comments on this
>>>>> feature please refer to the survey[2] that Brian posted few days ago.
>>>>>
>>>>> Maurizio
>>>>>
>>>>> [1] - http://cr.openjdk.java.net/~chegar/docs/sandbox.html
>>>>> [2] -
>>>>> http://mail.openjdk.java.net/pipermail/platform-jep-discuss/2016-March/000037.html 
>>>>>
>>>>>
>>>
>>
>