Best way to convert a Ruby string range to a Range object

Question

I have some Ruby code which takes dates on the command line in the format:

-d 20080101,20080201..20080229,20080301

Which means I want to run for all dates between 20080201 and 20080229 (inclusive) and the other dates present in the list.

Given I can get the string 20080201..20080229 what is the best way to convert this to an instance of Range. Currently I am using eval, but it feels like there should be a better way.

@Purfideas I was kind of looking for a more general answer for converting any string of type int..int to a Range I guess.

Answer 1

assuming you want the range to iterate properly through months etc, try

require 'date'

ends = '20080201..20080229'.split('..').map{|d| Date.parse(d)}
(ends[0]..ends[1]).each do |d|
  p d.day
end

Answer 2

But then just do

ends = '20080201..20080229'.split('..').map{|d| Integer(d)}
ends[0]..ends[1]

anyway I don't recommend eval, for security reasons

Answer 3

Inject with no args works well for two element arrays:

rng='20080201..20080229'.split('..').inject { |s,e| s.to_i..e.to_i }

Of course, this can be made generic

class Range
  def self.from_ary(a)
    a.inject{|s,e| [s..e]}
  end
end

rng = Range.from_ary('20080201..20080229'.split('..').map{|s| s.to_i})

Answer 4

Range.new(*self.split("..").map{|s|s.to_i})