ruby-dev summary 21403-21530

Hi all,

This is a summary of ruby-dev ML in these days.

[ruby-dev:21416] return value of #warn

  In current 1.8, #warn returns its argument.  U.Nakamura
  reported that #warn returns undetermined value on -W0.
  The return value was fixed to nil.

[ruby-dev:21176] marshalling ivtbl of Time

  In old 1.8, ruby did not dump instance variables if #_dump or
  #marshal_dump is defined.  Almost all built-in classes do not
  have #_dump/#marshal_dump, except the Time class (it has #_dump).
  So instance variables of Time objects will not be dumped. e.g.

    % ruby -ve '
        t = Time.now
        t.instance_eval { @ivar = 3 }
        Marshal.load(Marshal.dump(t)).instance_eval { p @ivar }
    '
    ruby 1.8.0 (2003-08-10) [i686-linux]    # != 1.8.0 release (2003-08-04)
    -e:3: warning: instance variable @ivar not initialized
    nil

  Matz decided to dump/restore instance variables automatically,
  even if #_dump/#marshal_dump is defined.  But it causes needless
  errors when trying to dump objects which include unserializable
  objects, e.g. IO.  Then if an object has #_dump/#marshal_dump
  and meets unserializable objects, ruby will not raise exception,
  just ignore it.  See following example for changes.

    % cat marshal_io
    class C
      def initialize
	@io = STDIN
	@n = 99
      end
      def marshal_dump
	3
      end
      def marshal_load( obj )
	@io = STDIN
      end
    end
    c = C.new
    p c
    p Marshal.load(Marshal.dump(c))


    % ruby-1.8.0 marshal_io
    #<C:0x401ace1c @io=#<IO:0x401b3280>, @n=99>
    #<C:0x401accc8 @io=#<IO:0x401b3280>>      # @n is not restored

    % ruby-HEAD marshal_io
    #<C:0x40270e1c @n=99, @io=#<IO:0x40277294>>
    #<C:0x40270cc8 @n=99, @io=#<IO:0x40277294>>

[ruby-dev:21498] {test,lib}/ChangeLog?

  Now ChangeLog file contains ruby's whole changes, including
  test/*, lib/*, ext/*, etc.  But there are other schemes of logging,
  e.g. one file per one directory.  NAKAMURA Hiroshi asked what our
  scheme should be; where to log for test scripts, for example.

  Matz replied that he prefers one ChangeLog file.

[ruby-dev:21508] eval BEGIN/END at runtime

  NAKAMURA Hiroshi asked how appropriate is current BEGIN/END block
  behavior.  See following script:

    eval 'BEGIN { puts "begin" }
          END { puts "end" }'
    puts '----'

  Ruby prints "begin", "----", then "end".  So, when we execute
  BEGIN/END in eval, BEGIN block is executed at the beginning of
  eval, END block is executed at the end of ruby process.

  Matz replied that this is a feature.


-- Minero Aoki