Try splatter operator for an IO.

splatter-case-when.rb

#!/usr/bin/env ruby
# vim: set fileencoding=utf-8 :
$VERBOSE = true

##DIDN'T WORK!!##
#see( Japanese ) http://www.ruby-lang.org/ja/man/html/_C0A9B8E6B9BDC2A4.html#case
print 'foo/bar/hoge: '
case gets #no chomp
when *DATA
  puts 'former when caluse.'
when "foo\n"
  puts 'latter when caluse.'
else
  puts 'no match.'
end

__END__
foo
bar
hoge

splatter-puts.rb

#!/usr/bin/env ruby
# vim: set fileencoding=utf-8 :
$VERBOSE = true
=begin
Try splatter operator for an IO.
=end

def same_with_puts *args
  puts( *args )
end

#Prepare the diffrence
same_with_puts( DATA )
same_with_puts( *DATA )

__END__
foo
bar
hoge