rubycocoa-talk

[Rubycocoa-talk] return simple int from Ruby to ObjC

[Motohiro T. <mo...@gm...>]

Hi,

I'm wondering how to return simple "int" type value from Ruby code to
Objective-C code.
Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
instead of simple int.
Any suggestion ?


Ruby code:

  class Hoge < OSX::NSObject
    def getInt
      5
    end
  end


Objective-C code:

	Class helper = NSClassFromString(@"Hoge");
	id hoge = [[helper alloc] init];
	NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge getInt]
decimalValue]);


and those show:

  2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448


thanks,

--
Motohiro Takayama
http://blog.deadbeaf.org/

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Laurent S. <lsa...@ap...>]

When creating a Ruby method like this, without providing its ObjC  
runtime signature, RubyCocoa will assume that all arguments and the  
return value are Objective-C objects (of the type 'id'). Because there  
is no way for RubyCocoa to know. This is why you get from the ObjC  
world an NSNumber and not an "int".

To work around this, you need to register the Ruby method into the  
ObjC runtime:

   def getInt ... end
   objc_method :getInt, 'int'

This will register getInt as a method that doesn't take any argument  
and returns a C integer.

Usually when you are overriding an ObjC method from Ruby, or  
implementing an ObjC informal protocol in Ruby, you don't need to use  
objc_method. But in this special case, it is required. Fortunately,  
most people won't need to use it.

Laurent

On Jul 15, 2007, at 3:01 PM, Motohiro Takayama wrote:

> Hi,
>
> I'm wondering how to return simple "int" type value from Ruby code to
> Objective-C code.
> Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
> instead of simple int.
> Any suggestion ?
>
>
> Ruby code:
>
>  class Hoge < OSX::NSObject
>    def getInt
>      5
>    end
>  end
>
>
> Objective-C code:
>
> 	Class helper = NSClassFromString(@"Hoge");
> 	id hoge = [[helper alloc] init];
> 	NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge getInt]
> decimalValue]);
>
>
> and those show:
>
>  2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448
>
>
> thanks,
>
> --
> Motohiro Takayama
> http://blog.deadbeaf.org/
>
> -------------------------------------------------------------------------
> This SF.net email is sponsored by DB2 Express
> Download DB2 Express C - the FREE version of DB2 express and take
> control of your XML. No limits. Just data. Click to get it now.
> http://sourceforge.net/powerbar/db2/
> _______________________________________________
> Rubycocoa-talk mailing list
> Rub...@li...
> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Motohiro T. <mo...@gm...>]

Laurent:

Thanks for your quick reply.

I tried your advice, and observed strange behavior.

class Hoge < OSX::NSObject
	objc_method :getInt, 'int'
	def getInt
		5
	end
end

and when call this, NSLog shows:

2007-07-15 22:50:15.667 retval[7097] XXX returning ffi type void for
unrecognized encoding 'nt'

I'm wondering why "i" of int is lack...

2007/7/15, Laurent Sansonetti <lsa...@ap...>:
> When creating a Ruby method like this, without providing its ObjC
> runtime signature, RubyCocoa will assume that all arguments and the
> return value are Objective-C objects (of the type 'id'). Because there
> is no way for RubyCocoa to know. This is why you get from the ObjC
> world an NSNumber and not an "int".
>
> To work around this, you need to register the Ruby method into the
> ObjC runtime:
>
>    def getInt ... end
>    objc_method :getInt, 'int'
>
> This will register getInt as a method that doesn't take any argument
> and returns a C integer.
>
> Usually when you are overriding an ObjC method from Ruby, or
> implementing an ObjC informal protocol in Ruby, you don't need to use
> objc_method. But in this special case, it is required. Fortunately,
> most people won't need to use it.
>
> Laurent
>
> On Jul 15, 2007, at 3:01 PM, Motohiro Takayama wrote:
>
> > Hi,
> >
> > I'm wondering how to return simple "int" type value from Ruby code to
> > Objective-C code.
> > Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
> > instead of simple int.
> > Any suggestion ?
> >
> >
> > Ruby code:
> >
> >  class Hoge < OSX::NSObject
> >    def getInt
> >      5
> >    end
> >  end
> >
> >
> > Objective-C code:
> >
> >       Class helper = NSClassFromString(@"Hoge");
> >       id hoge = [[helper alloc] init];
> >       NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge getInt]
> > decimalValue]);
> >
> >
> > and those show:
> >
> >  2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448
> >
> >
> > thanks,
> >
> > --
> > Motohiro Takayama
> > http://blog.deadbeaf.org/
> >
> > -------------------------------------------------------------------------
> > This SF.net email is sponsored by DB2 Express
> > Download DB2 Express C - the FREE version of DB2 express and take
> > control of your XML. No limits. Just data. Click to get it now.
> > http://sourceforge.net/powerbar/db2/
> > _______________________________________________
> > Rubycocoa-talk mailing list
> > Rub...@li...
> > https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>
>
> -------------------------------------------------------------------------
> This SF.net email is sponsored by DB2 Express
> Download DB2 Express C - the FREE version of DB2 express and take
> control of your XML. No limits. Just data. Click to get it now.
> http://sourceforge.net/powerbar/db2/
> _______________________________________________
> Rubycocoa-talk mailing list
> Rub...@li...
> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Laurent S. <lsa...@ap...>]

Oops, please try

   objc_method :getInt, ['int']

The second argument of objc_method is supposed to be an Array. I will  
fix the method to accept a String.

Laurent

On Jul 15, 2007, at 3:55 PM, Motohiro Takayama wrote:

> Laurent:
>
> Thanks for your quick reply.
>
> I tried your advice, and observed strange behavior.
>
> class Hoge < OSX::NSObject
> 	objc_method :getInt, 'int'
> 	def getInt
> 		5
> 	end
> end
>
> and when call this, NSLog shows:
>
> 2007-07-15 22:50:15.667 retval[7097] XXX returning ffi type void for
> unrecognized encoding 'nt'
>
> I'm wondering why "i" of int is lack...
>
> 2007/7/15, Laurent Sansonetti <lsa...@ap...>:
>> When creating a Ruby method like this, without providing its ObjC
>> runtime signature, RubyCocoa will assume that all arguments and the
>> return value are Objective-C objects (of the type 'id'). Because  
>> there
>> is no way for RubyCocoa to know. This is why you get from the ObjC
>> world an NSNumber and not an "int".
>>
>> To work around this, you need to register the Ruby method into the
>> ObjC runtime:
>>
>>   def getInt ... end
>>   objc_method :getInt, 'int'
>>
>> This will register getInt as a method that doesn't take any argument
>> and returns a C integer.
>>
>> Usually when you are overriding an ObjC method from Ruby, or
>> implementing an ObjC informal protocol in Ruby, you don't need to use
>> objc_method. But in this special case, it is required. Fortunately,
>> most people won't need to use it.
>>
>> Laurent
>>
>> On Jul 15, 2007, at 3:01 PM, Motohiro Takayama wrote:
>>
>>> Hi,
>>>
>>> I'm wondering how to return simple "int" type value from Ruby code  
>>> to
>>> Objective-C code.
>>> Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
>>> instead of simple int.
>>> Any suggestion ?
>>>
>>>
>>> Ruby code:
>>>
>>> class Hoge < OSX::NSObject
>>>   def getInt
>>>     5
>>>   end
>>> end
>>>
>>>
>>> Objective-C code:
>>>
>>>      Class helper = NSClassFromString(@"Hoge");
>>>      id hoge = [[helper alloc] init];
>>>      NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge  
>>> getInt]
>>> decimalValue]);
>>>
>>>
>>> and those show:
>>>
>>> 2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448
>>>
>>>
>>> thanks,
>>>
>>> --
>>> Motohiro Takayama
>>> http://blog.deadbeaf.org/
>>>
>>> -------------------------------------------------------------------------
>>> This SF.net email is sponsored by DB2 Express
>>> Download DB2 Express C - the FREE version of DB2 express and take
>>> control of your XML. No limits. Just data. Click to get it now.
>>> http://sourceforge.net/powerbar/db2/
>>> _______________________________________________
>>> Rubycocoa-talk mailing list
>>> Rub...@li...
>>> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>>
>>
>> -------------------------------------------------------------------------
>> This SF.net email is sponsored by DB2 Express
>> Download DB2 Express C - the FREE version of DB2 express and take
>> control of your XML. No limits. Just data. Click to get it now.
>> http://sourceforge.net/powerbar/db2/
>> _______________________________________________
>> Rubycocoa-talk mailing list
>> Rub...@li...
>> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>>
>
> -------------------------------------------------------------------------
> This SF.net email is sponsored by DB2 Express
> Download DB2 Express C - the FREE version of DB2 express and take
> control of your XML. No limits. Just data. Click to get it now.
> http://sourceforge.net/powerbar/db2/
> _______________________________________________
> Rubycocoa-talk mailing list
> Rub...@li...
> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Motohiro T. <mo...@gm...>]

Right, I got correct return value !

thank you for your help.

2007/7/15, Laurent Sansonetti <lsa...@ap...>:
> Oops, please try
>
>    objc_method :getInt, ['int']
>
> The second argument of objc_method is supposed to be an Array. I will
> fix the method to accept a String.
>
> Laurent
>
> On Jul 15, 2007, at 3:55 PM, Motohiro Takayama wrote:
>
> > Laurent:
> >
> > Thanks for your quick reply.
> >
> > I tried your advice, and observed strange behavior.
> >
> > class Hoge < OSX::NSObject
> >       objc_method :getInt, 'int'
> >       def getInt
> >               5
> >       end
> > end
> >
> > and when call this, NSLog shows:
> >
> > 2007-07-15 22:50:15.667 retval[7097] XXX returning ffi type void for
> > unrecognized encoding 'nt'
> >
> > I'm wondering why "i" of int is lack...
> >
> > 2007/7/15, Laurent Sansonetti <lsa...@ap...>:
> >> When creating a Ruby method like this, without providing its ObjC
> >> runtime signature, RubyCocoa will assume that all arguments and the
> >> return value are Objective-C objects (of the type 'id'). Because
> >> there
> >> is no way for RubyCocoa to know. This is why you get from the ObjC
> >> world an NSNumber and not an "int".
> >>
> >> To work around this, you need to register the Ruby method into the
> >> ObjC runtime:
> >>
> >>   def getInt ... end
> >>   objc_method :getInt, 'int'
> >>
> >> This will register getInt as a method that doesn't take any argument
> >> and returns a C integer.
> >>
> >> Usually when you are overriding an ObjC method from Ruby, or
> >> implementing an ObjC informal protocol in Ruby, you don't need to use
> >> objc_method. But in this special case, it is required. Fortunately,
> >> most people won't need to use it.
> >>
> >> Laurent
> >>
> >> On Jul 15, 2007, at 3:01 PM, Motohiro Takayama wrote:
> >>
> >>> Hi,
> >>>
> >>> I'm wondering how to return simple "int" type value from Ruby code
> >>> to
> >>> Objective-C code.
> >>> Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
> >>> instead of simple int.
> >>> Any suggestion ?
> >>>
> >>>
> >>> Ruby code:
> >>>
> >>> class Hoge < OSX::NSObject
> >>>   def getInt
> >>>     5
> >>>   end
> >>> end
> >>>
> >>>
> >>> Objective-C code:
> >>>
> >>>      Class helper = NSClassFromString(@"Hoge");
> >>>      id hoge = [[helper alloc] init];
> >>>      NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge
> >>> getInt]
> >>> decimalValue]);
> >>>
> >>>
> >>> and those show:
> >>>
> >>> 2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448
> >>>
> >>>
> >>> thanks,
> >>>
> >>> --
> >>> Motohiro Takayama
> >>> http://blog.deadbeaf.org/
> >>>
> >>> -------------------------------------------------------------------------
> >>> This SF.net email is sponsored by DB2 Express
> >>> Download DB2 Express C - the FREE version of DB2 express and take
> >>> control of your XML. No limits. Just data. Click to get it now.
> >>> http://sourceforge.net/powerbar/db2/
> >>> _______________________________________________
> >>> Rubycocoa-talk mailing list
> >>> Rub...@li...
> >>> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
> >>
> >>
> >> -------------------------------------------------------------------------
> >> This SF.net email is sponsored by DB2 Express
> >> Download DB2 Express C - the FREE version of DB2 express and take
> >> control of your XML. No limits. Just data. Click to get it now.
> >> http://sourceforge.net/powerbar/db2/
> >> _______________________________________________
> >> Rubycocoa-talk mailing list
> >> Rub...@li...
> >> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
> >>
> >
> > -------------------------------------------------------------------------
> > This SF.net email is sponsored by DB2 Express
> > Download DB2 Express C - the FREE version of DB2 express and take
> > control of your XML. No limits. Just data. Click to get it now.
> > http://sourceforge.net/powerbar/db2/
> > _______________________________________________
> > Rubycocoa-talk mailing list
> > Rub...@li...
> > https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>
>
> -------------------------------------------------------------------------
> This SF.net email is sponsored by DB2 Express
> Download DB2 Express C - the FREE version of DB2 express and take
> control of your XML. No limits. Just data. Click to get it now.
> http://sourceforge.net/powerbar/db2/
> _______________________________________________
> Rubycocoa-talk mailing list
> Rub...@li...
> https://lists.sourceforge.net/lists/listinfo/rubycocoa-talk
>

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Satoshi N. <sna...@in...>]

Hi Laurent.

>    objc_method :getInt, ['int']
>
> The second argument of objc_method is supposed to be an Array. I will  
> fix the method to accept a String.

I think it might be difficult.
Because the second argument accepts a string in raw encodings like 'i@:'.

--
Satoshi Nakagawa


On 2007/07/15, at 22:58, Laurent Sansonetti wrote:

> Oops, please try
>
>    objc_method :getInt, ['int']
>
> The second argument of objc_method is supposed to be an Array. I will  
> fix the method to accept a String.
>
> Laurent
>
> On Jul 15, 2007, at 3:55 PM, Motohiro Takayama wrote:
>
>> Laurent:
>>
>> Thanks for your quick reply.
>>
>> I tried your advice, and observed strange behavior.
>>
>> class Hoge < OSX::NSObject
>> 	objc_method :getInt, 'int'
>> 	def getInt
>> 		5
>> 	end
>> end
>>
>> and when call this, NSLog shows:
>>
>> 2007-07-15 22:50:15.667 retval[7097] XXX returning ffi type void for
>> unrecognized encoding 'nt'
>>
>> I'm wondering why "i" of int is lack...
>>
>> 2007/7/15, Laurent Sansonetti <lsa...@ap...>:
>>> When creating a Ruby method like this, without providing its ObjC
>>> runtime signature, RubyCocoa will assume that all arguments and the
>>> return value are Objective-C objects (of the type 'id'). Because  
>>> there
>>> is no way for RubyCocoa to know. This is why you get from the ObjC
>>> world an NSNumber and not an "int".
>>>
>>> To work around this, you need to register the Ruby method into the
>>> ObjC runtime:
>>>
>>>   def getInt ... end
>>>   objc_method :getInt, 'int'
>>>
>>> This will register getInt as a method that doesn't take any argument
>>> and returns a C integer.
>>>
>>> Usually when you are overriding an ObjC method from Ruby, or
>>> implementing an ObjC informal protocol in Ruby, you don't need to use
>>> objc_method. But in this special case, it is required. Fortunately,
>>> most people won't need to use it.
>>>
>>> Laurent
>>>
>>> On Jul 15, 2007, at 3:01 PM, Motohiro Takayama wrote:
>>>
>>>> Hi,
>>>>
>>>> I'm wondering how to return simple "int" type value from Ruby code  
>>>> to
>>>> Objective-C code.
>>>> Ruby code passes Fixnum, and Objective-C code recieves NSCFNumber
>>>> instead of simple int.
>>>> Any suggestion ?
>>>>
>>>>
>>>> Ruby code:
>>>>
>>>> class Hoge < OSX::NSObject
>>>>   def getInt
>>>>     5
>>>>   end
>>>> end
>>>>
>>>>
>>>> Objective-C code:
>>>>
>>>>      Class helper = NSClassFromString(@"Hoge");
>>>>      id hoge = [[helper alloc] init];
>>>>      NSLog(@"%@ %d", [[hoge getInt] class], [(NSNumber *)[hoge  
>>>> getInt]
>>>> decimalValue]);
>>>>
>>>>
>>>> and those show:
>>>>
>>>> 2007-07-15 21:52:56.954 retval[5100] NSCFNumber 8448
>>>>
>>>>
>>>> thanks,
>>>>
>>>> --
>>>> Motohiro Takayama
>>>> http://blog.deadbeaf.org/

Re: [Rubycocoa-talk] return simple int from Ruby to ObjC

[Laurent S. <lsa...@ap...>]

On Jul 15, 2007, at 5:19 PM, Satoshi Nakagawa wrote:

> Hi Laurent.
>
>>   objc_method :getInt, ['int']
>>
>> The second argument of objc_method is supposed to be an Array. I will
>> fix the method to accept a String.
>
> I think it might be difficult.
> Because the second argument accepts a string in raw encodings like  
> 'i@:'.

True, I also figured that. Let's keep the current behavior. Looks like  
I wrote too fast :-)

Laurent