From: westlin9@...
Date: 2007-07-20T21:20:01+09:00
Subject: Re: block_given? problem

On 20 Juli, 14:04, "Robert Dober" <robert.do...@gmail.com> wrote:
> On 7/20/07, westl...@gmail.com <westl...@gmail.com> wrote:
>
>
>
> > I can't figure out why the do...end block isn't detected by the
> > "block_given?" function. The problem occurs when a method call with a
> > block is used in a puts statement. See the code example below.
> > Can some one explain this to me please? Is this a bug?
>
> > class TheClass
> >   def self.TheMethod()
> >     if block_given?
> >       puts "yes, block given"
> >     else
> >       puts "no block is given"
> >     end
> >     'return val'
> >   end
> > end
>
> > # ok
> > puts TheClass.TheMethod {|param| 123}
>
> > # block not detected
> > puts TheClass.TheMethod do |param|
> >   123
> > end
>
> > # ok
> > a = TheClass.TheMethod {|param| 123}
> > puts a
>
> > # ok
> > a = TheClass.TheMethod do |param|
> >   123
> > end
> > puts a
>
>  puts( TheClass.TheMethod do nil end )
>
> do...end and {} do not have the same precedence, thus, without the ()
> you are doing this
> puts( TheClass.TheMethod ) do nil end
>
> HTH
> Robert
>
> --
> I always knew that one day Smalltalk would replace Java.
> I just didn't know it would be called Ruby
> -- Kent Beck- D�lj citerad text -
>
> - Visa citerad text -

Thanks