# File lib/pry/pager.rb, line 136
    def self.available?
      if @system_pager.nil?
        @system_pager = begin
          pager_executable = default_pager.split(' ').first
          `which #{pager_executable}`
          $?.success?
        rescue
          false
        end
      else
        @system_pager
      end
    end