From: Josef 'Jupp' Schugt <jupp@...>
Date: 2003-03-19T05:37:40+09:00
Subject: Re: Accessing hash values sorted by their keys

Hi!

* On 2003-03-17 22:04
* Josef 'Jupp' Schugt <jupp@gmx.de> wrote:
> h.keys.sort.each { |key|
>   puts h[key]
> }

Thanks for the different alternatives for that. I think that

h.sort.each { |key, value|
  puts value
}

is the best version but different people prefer different coding
styles. Actually the method that did entrouble me was:

def print_sorted(hash, keys, separator)
  i = 0
  while i < keys.length
    x = hash[keys[i]]
    if x.nil?
      puts "-"
    else
      print separator unless i == 0
      print x.empty? ? '-' : x.join(', ')
    end
    i += 1
  end
end

It was used in a script that illustrates the use of Periodic.rb. the
hash contains all language versions of an elements name where. The
language versions in turn are arrays because in some languages there
is more than only one name for certain elements. The proposed
solution did help me condense the above code to:

def print_sorted(hash, separator)
  print hash.sort.map { |key, value|
      (value.nil? or value.empty?) ? '-' : value.join(', ')
  }.join(separator)
end

To me that looks more readable than the original version.

Josef 'Jupp' Schugt
-- 
jupp (AT) gmx (DOT) de                             :.          .....:
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http://jupp.tux.nu                                 ::::::::::::::::::
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