Bug: `Class`.forName doesn't work

[Wei Liu]

Loop is beautiful language, easy to learn and powerful at concurrency.

Thanks Dhanji,

When I played with loop, I found the following issue, please take a look.

>> `Class`.forName("java.lang.String").newInstance()
`Class`.forName("java.lang.String").newInstance()
Exception in thread "main" java.lang.VerifyError: (class: _shell, method: main signature: ()Ljava/lang/Object;) Incompatible argument to function
    at java.lang.Class.getDeclaredMethods0(Native Method)
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
    at java.lang.Class.getDeclaredMethod(Class.java:1935)
    at loop.Executable.main(Executable.java:230)
    at loop.Loop.safeEval(Loop.java:63)
    at loop.LoopShell.evalInFunction(LoopShell.java:275)
    at loop.LoopShell.shell(LoopShell.java:190)
    at loop.Loop.main(Loop.java:20)

[Dhanji R. Prasanna]

Thank you so much for the kind words!

You can achieve the same result by doing:

`java.lang.String`.newInstance()

This actually performs the Class.forName() for you underneath (and at compile time). Can you plz file a bug for this particular report, however? I will then chase it up.

[Wei Liu]

post an issue on github.

Look forward to your fix.

[Wei Liu]

I have found the root cause and issued a pull request on github.

Please take a look.

Cheers,
Leo

[Dhanji R. Prasanna]

Hi, the correct statement is:

`java.lang.String`.class.newInstance()

The chained Class.forName() is actually generating the wrong bytecode so your bugfix in Caller.java won't work I'm afraid =( I.e. it is not valid bytecode, so the JVM won't even load the loop program. I will have a closer look and try to fix it, in the meantime plz try my example above.

Dhanji.

[Dhanji R. Prasanna]

OK I have fixed this problem, it was actually a parser-problem, Loop was incorrectly treating the entire call chain as static instead of just the first method.

[Wei Liu]

The problem is still not fix completely, I tried the following scripts:

>> `java.util.GregorianCalendar`.class.newInstance().getClass()
java.util.GregorianCalendar
>> `java.util.GregorianCalendar`.class.newInstance().getTime()
java.util.GregorianCalendar
>> `java.util.GregorianCalendar`.getClass().newInstance()  # this returns a String

>> `java.util.GregorianCalendar`.getClass().newInstance().getTime()
java.lang.RuntimeException: Method not found: java.lang.String#getTime([])
    at _shell.main(Unknown Source)

[Dhanji R. Prasanna]

Ahh I see what you're trying to do. Ok this has been fixed now, I've changed the API a bit:

`java.util.GregorianCalendar::class`.newInstance().getTime()

// you need to use the special form ::class to resolve the java literal into a class.

Plz let me know if this works.