mysterious behaviour

[bblochl2-2]

I tried the example "Create a simple object and show how to use it" from the page http://www.iolanguage.com/about/samplecode/:


Account := Object clone do(
    balance := 0
    deposit  := method(v, balance = balance + v)
    withdraw := method(v, balance = balance - v)
    show := method(writeln("Account balance: ", balance))
)

myAccount := Account clone
myAccount show
"Depositing $10\n" print
myAccount deposit(10)
myAccount show

If I try to deposit I get:

Io> myAccount deposit(100)

  Exception: Account does not respond to 'deposit'
  ---------
  Account deposit                      Command Line 1

And if I try show, I get :

Io> myAccount show

  Exception: Account does not respond to 'show'
  ---------
  Account show                         Command Line 1

And if I try to access the deposit slot I get an endless loop and have to break the Io interpreter by CTRL+D.

Where is my error?

Thanks BB

There are some erors in the example on the page http://wiki.type-z.org/index.php/Io/IoLanguage as wel, as the necessary sign sign := is used = alone - that does not work! Easy to find, but not for beginners with Io,

HelloObject = Object clone
  HelloObject sayHello = method(
     "Hello World!" print
  )
  HelloObject sayHello()

Does anybody know the admin of the page?

[bblochl2-2]

--- In iolanguage@..., "bblochl2" <bblochl2@...> wrote:

>
> I tried the example "Create a simple object and show how to use it" from the page http://www.iolanguage.com/about/samplecode/:
>
>
> Account := Object clone do(
>     balance := 0
>     deposit  := method(v, balance = balance + v)
>     withdraw := method(v, balance = balance - v)
>     show := method(writeln("Account balance: ", balance))
> )
>
> myAccount := Account clone
> myAccount show
> "Depositing $10\n" print
> myAccount deposit(10)
> myAccount show
>
> If I try to deposit I get:
>
> Io> myAccount deposit(100)
>
>   Exception: Account does not respond to 'deposit'
>   ---------
>   Account deposit                      Command Line 1
>
> And if I try show, I get :
>
> Io> myAccount show
>
>   Exception: Account does not respond to 'show'
>   ---------
>   Account show                         Command Line 1
>
> And if I try to access the deposit slot I get an endless loop and have to break the Io interpreter by CTRL+D.
>
> Where is my error?
>
> Thanks BB
>
> There are some erors in the example on the page http://wiki.type-z.org/index.php/Io/IoLanguage as wel, as the necessary sign sign := is used = alone - that does not work! Easy to find, but not for beginners with Io,
>
> HelloObject = Object clone
>   HelloObject sayHello = method(
>      "Hello World!" print
>   )
>   HelloObject sayHello()
>
> Does anybody know the admin of the page?
>

I just tried the above Account example as a script with a starting shebang line on Linux - it was working! First I tried it from the Io line interpreter with the described results. I tried some other programs in the meantime as well. Just if I use that d() construct for declaration of prototypes with more than one line I get such infinite loop troubles with high frequency accesses to the harddisk with a work overload and short time (seconds) interruption of any other running programs. A prototype with just one line atrribute or method will work ok.

May be there is something wrong with the Io line interpreter with the Linux version? A separator problem? May be the line break encoding problem for different OSes?

Regards BB

[Brian Mitchell]

On Mon, Jul 13, 2009 at 14:32, bblochl2<bblochl2@...> wrote:
> May be there is something wrong with the Io line interpreter with the Linux
> version? A separator problem? May be the line break encoding problem for
> different OSes?

I haven't had time to try things out but have you tried using one line
with ;'s on the REPL? I think the interactive REPL is a little broken
on some inputs.

Brian.

[Oscar Martinez]

--- In iolanguage@..., "bblochl2" <bblochl2@...> wrote:
>
>
> I just tried the above Account example as a script with a starting shebang line on Linux - it was working! First I tried it from the Io line interpreter with the described results. I tried some other programs in the meantime as well. Just if I use that d() construct for declaration of prototypes with more than one line I get such infinite loop troubles with high frequency accesses to the harddisk with a work overload and short time (seconds) interruption of any other running programs. A prototype with just one line atrribute or method will work ok.
>
> May be there is something wrong with the Io line interpreter with the Linux version? A separator problem? May be the line break encoding problem for different OSes?
>
> Regards BB
>

Playing with the CLI I found that Z_CLI.io does not handle correctly that case and the "slash at the end" case, at lease in my box (Debian Squeze/Sid on amd64).

Touching a pair of lines solved the problem for me.

I have setup a github repo so so an expert can examine:

http://github.com/omf/io/tree/cli

Regards