# File lib/more/facets/tuple.rb, line 244
    def cast_from_string( str, &yld )
      args = str.to_s.split(/\W+/)
      div = /\W+/.match( str.to_s )[0]
      if block_given?
        args = args.collect{ |a| yld[a] }
      else
        args = args.collect { |i| /^[0-9]+$/ =~ i ? i.to_i : i }
      end
      self.instance( args ).divider( div )
    end