Contents

module Alf
  class Reader
    #
    # Specialization of the Reader contract for .rash files.
    #
    # A .rash file/stream contains one ruby hash literal on each line. This reader simply
    # decodes each of them in turn with Kernel.eval, providing a state-less reader (that
    # is, tuples are not all loaded in memory at once).
    #
    class Rash < Reader

      def self.mime_type
        nil
      end

      # (see Reader#line2tuple)
      def line2tuple(line)
        return nil if line.strip.empty?
        begin
          h = Kernel.eval(line)
          raise "Tuple expected, got `#{h.inspect}`" unless TupleLike===h
        rescue Exception => ex
          $stderr << "Skipping `#{line.strip}`: #{ex.message}\n"
          nil
        else
          return h
        end
      end

      # Register .rash files for Relation loading
      Path.register_loader('.rash'){|file|
        Alf::Reader::Rash.new(file).to_a
      }

      Reader.register(:rash, [".rash"], self)
    end # class Rash
  end # class Reader
end # module Alf

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
alf-core-0.16.3	lib/alf/reader/rash.rb
alf-core-0.16.2	lib/alf/reader/rash.rb
alf-core-0.16.1	lib/alf/reader/rash.rb
alf-core-0.16.0	lib/alf/reader/rash.rb