On Sun, Apr 13, 2008 at 12:04 PM, Trans <transfire / gmail.com> wrote:
>
>
>  On Apr 13, 4:58 am, "Robert Dober" <robert.do... / gmail.com> wrote:
>
>
> > On Sun, Apr 13, 2008 at 2:51 AM, ara.t.howard <ara.t.how... / gmail.com> wrote:
>  >
>  > >  On Apr 12, 2008, at 5:12 PM, Trans wrote:
>  >
>  > > > Let see.... Facets:
>  >
>  > > >  class Hash
>  >
>  > > >   # Returns a new hash with only the given keys.
>  >
>  > > >   def slice(*keep_keys)
>  > > >     h = {}
>  > > >     keep_keys.each do |key|
>  > > >       h[key] = fetch(key)
>  > > >     end
>  > > >     h
>  > > >   end
>  >
>  > > >   # Replaces hash with a new hash having only the given keys.
>  > > >   # This return the hash of keys removed.
>  >
>  > > >   def slice!(*keep_keys)
>  > > >     removed = except(*keep_keys)
>  > > >     replace(slice(*keep_keys))
>  > > >     removed
>  > > >   end
>  >
>  > > >  end
>  >
>  > >  okay, you should add the block form ;-)
>  >
>  > >  headers.slice{|k,| k =~ %r/^HTTP_/}
>  >
>  > >  handy.....
>  >
>  > >  cheers.
>  >
>  > >  a @http://codeforpeople.com/
>  > >  --
>  > >  we can deny everything, except that we have the possibility of being
>  > > better. simply reflect on that.
>  > >  h.h. the 14th dalai lama
>  >
>  > Hmm maybe it is a more consistent approach not to add a block to slice.
>  >
>  > FWIAC, I use hselect, kselect and vselect, the simplified code
>  > goes like this (1) of course
>  >   def kselect  &blk
>  >       hselect{ |k,| blk.call(k) }
>  >   end
>  >
>  >   def vselect &blk
>  >       hselect{ |_,v| blk.call(v) }
>  >   end
>  >   def hselect &blk
>  >      #almost Tom's code of course
>  >   end
>
>  Why not?
>
>   hash.keys.select
>   hash.values.select
We were talking about getting sliced hashes not sliced key or value
arrays. Maybe in the future there will be a saying
"the best thing since the invention of sliced hashes by Ara T. Howard"
the real inventor gets always forgotten sorry for Facets I can not
change future history ;)
>
>
>  > You might write
>  >   h.slice(*[*1..10]){|k,v| whatever k, v }
>  > which indeed I like
>  >
>  > I would write
>  >    h.slice(*[*1..10]).hselect{|k,v| whatever k, v}
>  > which indeed I like less, *but* I dislike the inconsistency of #select now.
>  >
>  > The ideal solution might be to add a block to Enumerator#select too,
>  > what about that?
>
>  Hmm... I don't understand Enumerator#select comes from
>  Enumerable#select and already takes a block.
Stupid me *again* I meant Array#slice. I feel that my brain is
terribly disconnected from the keyboard, (I believe that Scotty was
right when talking into the mouse LOL). Well proofreading my posts
would be an option though :).

I will express myself in Ruby

assert_nothing_raised ("You see it would be nice that Array#slice and
Hash#slice had (almost) the same interface") do
[*1..100].slice(1..10){ |x| x.zero? }
end


Sorry
R.
-- 
http://ruby-smalltalk.blogspot.com/

---
Whereof one cannot speak, thereof one must be silent.
Ludwig Wittgenstein