[MacRuby-devel] Translating Obj-C to MacRuby

[John Shea]

Hi Bernd,

YES and NO in ObjC are translated to true and false in MacRuby.

so you were probably after:

  NSNumber.numberWithBool(false)

(I am curious as to how often that is useful actually)

I will leave the table idea for others to comment - I actually think  
in the end there are only a few rules to learn and then you will find  
yourself translating easily (not that those rules should not go in a  
cheat sheet somewhere - that's probably a good idea).

With:
NSDictionary.dictionaryWithObjectsAndKeys "a", "b", nil

I assume that in the original ObjC method is actually passing an array  
which (it seems) must be terminated by a nil (in objC).
I actually ran across this in another context - passing objects in  
this way - again I will leave others to comment on it, perhaps it is  
an issue.

However why can't you use :

dict = {"b"=>"a"}
=> {"b"=>"a"}

#check class of created dictionary
dict.class
=> NSMutableDictionary

Why use the long winded ObjC form?

If you need a immutable NSDictionary for some reason:
dict = NSDictionary.alloc.initWithDictionary({"a"=>"b", "c" => "d"})
#or if you like typing
dict = NSDictionary.dictionaryWithObjects(["b","d"], forKeys: 
["a","c"],count:1)

(and many other similar methods, I am sure) works fine.

Cheers,
John


On Oct 14, 2009, at 10:03 , B. Ohr wrote:

> Hi all!
>
> Using Cocoa in MacRuby is sometimes a hard job, because all  
> documentation, examples and sample code is Obj-C. For example, I  
> found this piece of code '[NSNumber numberWithBool:NO]' and asked  
> myself how to write that in Macruby.
>
> I opened macirb and typed:
>
> > NSNumber.numberWithBool 0
> => false
>
> First I had to laugh and then I thought: Hey implementors of  
> macruby, you really did a great job!
>
> What do you think about a table on http://www.macruby.org/ which  
> lists all such short (and astonishing) examples. Or even better, why  
> not create a command in the services menu which translates a Obj-C  
> sequence (by regexp).
>
> BTW, the second example I tried is:
>
> > NSDictionary.dictionaryWithObjectsAndKeys "a", "b", nil
>
> but instead of {"b"=>"a"} I got a seg fault! (ticket is filed)
>
> Greets,
> Bernd
>
>
>
>
>
> _______________________________________________
> MacRuby-devel mailing list
> MacRuby-devel at lists.macosforge.org
> http://lists.macosforge.org/mailman/listinfo.cgi/macruby-devel

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