如何在Ruby中将一个范围为的值字符串转换为一个数组

"12,3-5,2,6".
  gsub(/(\d+)-(\d+)/) { ($1..$2).to_a.join(',') }.
  split(',').
  map(&:to_i)
#⇒ [12, 3, 4, 5, 2, 6]

"1,3,6-8,5".split(',').map do |str|
  if matched = str.match(/(\d+)\-(\d+)/)
    (matched[1].to_i..matched[2].to_i).to_a
  else
    str.to_i
  end
end.flatten

或

"1,3,6-8,5".split(',').each_with_object([]) do |str, output|
  if matched = str.match(/(\d+)\-(\d+)/)
    output.concat (matched[1].to_i..matched[2].to_i).to_a
  else
    output << str.to_i
  end
end

或严格

RANGE_PATTERN = /\A(\d+)\-(\d+)\z/
INT_PATTERN   = /\A\d+\z/

"1,3,6-8,5".split(',').each_with_object([]) do |str, output|
  if matched = str.match(RANGE_PATTERN)
    output.concat (matched[1].to_i..matched[2].to_i).to_a

  elsif str.match(INT_PATTERN)
    output << str.to_i

  else
    raise 'Wrong format given'
  end
end

"1,3,6-8,5".split(',').flat_map do |s|
  if s.include?('-')
    f,l = s.split('-').map(&:to_i)
    (f..l).to_a
  else
    s.to_i
  end
end.sort
  #=> [1, 3, 5, 6, 7, 8]

"1,3,6-8,5"
.scan(/(\d+)\-(\d+)|(\d+)/)
.flat_map{|low, high, num| num&.to_i || (low.to_i..high.to_i).to_a}
#=> [1, 3, 6, 7, 8, 5]