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That is to say, it does not have to be "shared" anymore. "Hello world" becomes: So `def main` can now be specified without `is shared` provided that the containing type has a parameterless initializer (so that it can be instantiated). And it can still be `shared` if that's required or desired.

Furthermore, `main` can no longer take arguments or return a value. Use `CobraCore.commandLineArgs` and `CobraCore.exit(code)` instead.

Finally, you can use the new -main: command line option to disambiguate when there is more than one `main` method. See cobra -h

This is in the repository. Any questions or problems, let me know.

is this case where 'is shared' is required?
I got Cobra.Lang.AssertException.

No.
The exception here is caused by the attribute testObject not being initialized after the constructor completes.
You'll note the assert failure goes away if you comment the

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var testObject as String

line

Also I suspect that what you're doing here isnt what you think you're doing :
You're declaring an attribute ( var testObject) that is not initialized and never used then
using a local variable ( testObject) in the main method
perhaps what you were thinking was to declare and use an instance attribute

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class Program
    var testObject as String

    def main
        .testObject = "Hello"   # note the leading '.'
        print .testObject


This will still assert exception cos testObject isnt initialized in the ( implicit default noArg constructor)
so you need this

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class Program
    var testObject as String

    cue init
        base.init   # required now
        .testObject = ''initted'     # this makes the assert exception go away

    def main
        .testObject = "Hello"   # note the leading '.'
        print .testObject


Chuck,
since this is now treating (def) main even more specially and applying some otherwise invisible wrapping around its handling shouldnt this
become

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cue main

to be logically consistent with the other special use/case/handling def methods ( init, compareTo, hashcode,...) ??

Another approach is just to give a basic value to the variable in the declaration:
Another approach is to make the type nilable:

I often prefer the first because non-nilable variables are unlikely to cause null-ref exceptions at run-time (unless of course you don't initialize their value during declaration or cue.init). Of course, it would be nice if Cobra issued at least a warning for obvious cases that are going to fail.

Regarding "cue", the thing I found strange about "main" is that it is not really an object-oriented cue like .init or (the upcoming) .hash. It is program-oriented and really has no special effect on the object. In the end, I chose "def".

oops! I forgot period...
also, I learned necessity for initializing the attribute.

is 'is shared' hardly necessary anymore for main?

by the way,

This will still assert exception cos testObject isnt initialized in the ( implicit default noArg constructor)
so you need this

what "cos"?
"cos" is omitted phrase?

Thanks,

Correct, the "is shared" is no longer necessary. When absent, the class will be instantiated and its .main method invoked.

"cos" is slang for "because"

I tried IE Browser test.
In the following cases, should it be main is shared?
If it is main is not-shared, [System.STAThreadAttribute] is needed in MainWrapper.cobra.cs

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use System.Windows.Forms

class MyForm inherits Form
   var _txb as System.Windows.Forms.TextBox
   var _btn as System.Windows.Forms.Button
   var _web as System.Windows.Forms.WebBrowser
   
   cue init
      base.init
      .text = 'IE8 test'
      _txb = TextBox(parent=this, text="http://")
      _btn = Button(parent = this, text="go to site")
      _web = WebBrowser(parent = this)
      listen _btn.click, ref .handleClick
      
   def handleClick(sender, args as EventArgs)
      try
         _web.navigate(Uri(_txb.text))
      catch
         _txb.text = 'ERROR'
      
class Program
   def main has STAThread
      Application.run(MyForm())

So the attributes are not being carried over. Yes, you'll have to add "is shared" for now.

Would you enter a ticket for this?

I entrust you.
because knowledge for my ticket-system is shallow.
also, my English is strange.