# File lib/randexp/reducer.rb, line 68
    def self.whitespace(quantity)
      case quantity
      when '?''?'       then ['', Randgen.whitespace].pick
      when :+, '+?''+?'  then raise "Sorry, \"\\s+\" is too vague, try setting a range: \"\\s{1, 5}\""
      when :*, '*?''*?'  then raise "Sorry, \"\\s*\" is too vague, try setting a range: \"\\s{0, 5}\""
      when Range      then quantity.pick.of { Randgen.whitespace } * ''
      when Integer    then quantity.of { Randgen.whitespace } * ''
      when nil        then Randgen.whitespace
      end
    end