[ruby-talk:00503] FromJapan: #3

Hi folks!

In past four weeks, about 550 messages are posted to ruby-list <dizzy>. 
I was so busy and didn't follow almost all of them.... So, I've decide to
split into several issues. I also entrust the pick-up job to ruby.freak.ne.jp
which is a famous unofficial portal site for Ruby (in Japanese).

Today, I pick up 11 topics:

    Contrib
	[ruby-list:14843] Ruby/Tk TkText#dump
	[ruby-list:14960] http-access-0.0.2 managing HTTP/1.0 & HTTP/1.1
	[ruby-list:15042] Ruby package for Debian GNU/Linux
	[ruby-list:15056] mod_ruby-0.1.3 for Apache

    Q and A
	[ruby-list:14908] a method which is always called when GC?
	[ruby-list:14970] thread with curses

    Tips
	[ruby-list:14916] HEAD requesting to a `Keep-Alive' HTTP server. 
	[ruby-list:14972] embedding documet rd
	[ruby-list:15009] Re: detecting failure of str.to_i, str.to_f

    Fringe
	[ruby-list:14890] Object-Oriented Software Construction (2nd edition)
	[ruby-list:15064] `Hako iri Musume' in Ruby/TK

    ======================================================================
	Contrib  [ftp://ftp.netlab.co.jp/pub/lang/ruby/contrib/]
    ______________________________________________________________________

	[ruby-list:14843] Ruby/Tk TkText#dump

	Tomoyuki KOSHIMIZU wrote TkText#dump which corresponds to `text dump'
	of Tcl/Tk. This code has already been included in the released version.
    ______________________________________________________________________

	[ruby-list:14960] http-access-0.0.2 managing HTTP/1.0 & HTTP/1.1

	Takahiro MAEBASHI put http-access-0.0.2. It is result of Nahi's 
	patch and TAKAHASHI Masayoshi's patch for url-parse.rb. 
	This version supports

	- port number scheme of url
	- HTTP/1.0
	- responses from servers which use LF-only for HTTP header delimiter
    ______________________________________________________________________

	[ruby-list:15042] Ruby package for Debian GNU/Linux

	Good new for a Debian GNU/Linux user! 
	Debian's official site http://www.debian.org/ started distribing
	Ruby package. 
    ______________________________________________________________________

	[ruby-list:15056] mod_ruby-0.1.3 for Apache

	Shugo MAEDA put mod_ruby-0.1.3. Minor change only. 
	He also seeks someone who uses mod_ruby on RedHat. 

    ======================================================================
	Q and A
    ______________________________________________________________________

	[ruby-list:14908] a method which is always called when GC?

	Question:
		How can I define FOO#bye such that is always called 
		when each object of FOO would be GC?
		For example, does the following work?

class FOO
  require "final"

  def initialize(filename)
    @x = filename
    ObjectSpace.define_finalizer(self, lambda{bye})
  end

  def bye
    raise "gone" unless @x
    open(@x, "a+"){|f| f << $$ << ": bye\n"}
    @x = nil
  end
end

	Answer:
		No, it doesn't. If a proc which is generated in method's 
		context is passed to a finalizer, a reference from finalizer 
		to self is made. It is because of such object shall never 
		be garbage. 

		See Akira YAMADA's `tempfile.rb' for use of the finalizer. 
		In tempfile.rb, He devised as follows:

		* creating proc by a class method to avoid to refer self
		* giving needed information as options 

		Essentialy, GC and finalizer are ill-matched each other (why 
		did Java adopt?). So, the finalizer is made inconvenient on
		purpose. Maybe, Java-like finalizer will be adopted in future 
		but it's difficult to be efficient. 
    ______________________________________________________________________

	[ruby-list:14970] thread with curses

	Question:
		I'm trying to make code like `talk' which has two windows
		in a terminal: one of them is used to input and another to
		output by server. But `getstr' is called for input then 
		the program stop...

	Answer:
		Well, curses is not thread safe. I guess to check by IO:select
		and to input by getch as follows:

require "curses"
include Curses

module Curses
  class Window
    def get_str
      str = ""
      max = str.length
      line = cury
      col = curx
      catch(:CURSES_WINDOW_GET_STR) do
        loop do
          setpos(line, col)
          addstr(" " * max)
          setpos(line, col)
          addstr(str)
          refresh
          sleep(0.1) if (IO::select([ STDIN ]))
          case (c = getch)
          when ?\C-h
            str.chop!
          when ?\C-u
            str = ""
          when ?\n
            throw(:CURSES_WINDOW_GET_STR,
                  unless (str.empty?) then str end)
          when ?\C-g
            throw(:CURSES_WINDOW_GET_STR, nil)
          else
            str << c.chr
          end
          max = [ max, str.length ].max
        end
      end
    end
  end
end

init_screen

cbreak
noecho

max = lines - 3

output = Window.new( max, cols, 0, 0)
output.setpos( 0, 0)
input = Window.new( 2, cols, max + 1, 0)

Thread.start do
  i = 0
  while i < 100
    output.addstr( i.to_s + "\n")
    output.refresh
    sleep 1
    i += 1
  end
end

while TRUE
  input.setpos( 1, 0)
  input.addstr( "input > ")
  input.refresh
  # sleep 2
  tmp = input.get_str
  if tmp == "q"
    break
  end
  output.addstr( tmp + "\n")
  output.refresh
  input.clear
end

input.close
output.close

close_screen

    ======================================================================
	Tips
    ______________________________________________________________________
	
	[ruby-list:14916] HEAD requesting to a `Keep-Alive' HTTP server. 

	On HTTP. If an agent sents some requests in a time to a server, 
	using Keep-Alive is a smart solution. But some servers don't support 
	Keep-Alive. And furthermore, a agent cannot know whether the server 
	supports that or not, until getting server's response.

	The following solves such difficulty. The point is to check both
	`Status' and `Connection'.  (Suggested by Wakou AOYAMA who also
	wrote telnet.rb)

#!/usr/local/bin/ruby

require "socket"

CR  = "\015"
LF  = "\012"
EOL = CR + LF

def get_head(host, port, files)
  heads = {}
  sock = nil

  for i in 0 ... files.size

    if sock == nil or sock.closed?
      sock = TCPsocket.open(host, port)
      sock.binmode
      STDERR.print "server open.\n"
    end

    if i == files.size - 1
      connection = "Close"
    else
      connection = "Keep-Alive"
    end

    sock << "HEAD " << files[i] << " HTTP/1.1" << EOL
    sock << "Host: " << host << EOL
    sock << "Connection: " << connection << EOL
    sock << EOL

    status = sock.gets(LF)
    if CR == status[status.size - 2].chr
      eol = EOL
    else
      eol = LF
    end
    head = sock.gets(eol + eol)

    if (/Connection:\s+Close/ni === head) or
       ((/HTTP\/1\.0/ni === status) and
        (not /Connection:\s+Keep-Alive/ni === head))
      sock.close if not sock.closed?
    end

    heads[files[i]] = head
  end

  sock.close if not sock.closed?
  heads
end

port = "80"
host = "www.jin.gr.jp"
files = %w[ /~nahi/ /~nahi/Ruby/ /~nahi/link-Ruby.html ]
### Keep-Alive unavailable host:
#host = "www.isc.meiji.ac.jp"
#files = %w[ /~ee77038/ /~ee77038/ruby/index.html /~ee77038/ruby/program.htm ]
### HTTP 1.0 only host:
#host = "www2c.biglobe.ne.jp"
#files = %w[ / /~hosoda/ ]

get_head(host, port, files).each do |file, head|
  print file, "\n"
  print head
end
    ______________________________________________________________________

	[ruby-list:14972] embedding documet rd

	There is POD (plain old document) which is a comment style in
	Perl to generate online manual from the code by perl2man. 
	(See also perlpod(1)). Ruby has similar feature RD (ruby document). 
	Only ftp://ftp.netlab.co.jp/pub/lang/ruby/contrib/rd2html is known 
	as a tool to convert from this format. One can obtain the document of
	CGI.rb by rd2html. 

	RD features have been released in [ruby-dev:3045]. Matz said that 
	the manuscript of the first book about Ruby is described in this 
	format. 

	Heading
		= Chapter
		== Section
		=== Subsection

		+ Chapter without numbering
		++ Section without numbering
		+++ Subsection without numbering

	Listing
		* Let's list 
		* like this. 
		    * indent level
		    * is supported

	Enumerating
		(1) Let's list
		(2) like this. 
		(1) renumbering

	Definition
		: bar
			came from fubar (See `fubar')
		: foo
			came from fubar (See `fubar')
		: fubar
			(US Army) acronym of `fucked up beyond all repaired'

	Verbatim
			str = "TAB indented lines are regarded as code. "
			# sorry for difficulty to see

	Footnote
		RD is designed for a book. (-- coming soon in Japan! --)

	Terminology
		[-- class --] will be appeared in glossary.  
    ______________________________________________________________________

	[ruby-list:15009] Re: detecting failure of str.to_i, str.to_f

	String#to_i/to_f converts string into a numeic within the receiver 
	string can be regarded as an expression of numeric. But sometime 
	one wants to detect whether whole of string is numric or not. 
	For example

"12.3abc".to_i #=> 12
"12.3abc".to_f #=> 12.3

	whareas "12.3abc" itself is not an expression of any numeric. 
	(WATANABE Tetsuya pointed out that this spec from atoi() then Perl)

	ARIMA Yasuhiro wrote to_int/to_float which converts but raises error
	if the receiver string is not pure numeric exp. "It's not completed", 
	he comments, "but enough to my current problem".  Indeed, this regexp
	is not support freely appearance of `_' in the numeric literal. 

class String
  def to_float
    return to_f if self =~ /^[-+]?((\d+)?(\.\d+))|((\d+)(\.\d+)?)([eE][-+]\d+)?$/
    raise "fail at convert string to float"
  end
  def to_int
    return to_i if self =~ /^[-+]?(\d+)$/
    raise "fail at convert string to int"
  end
end

if __FILE__ == $0
  def c x
      begin
	x.to_s.to_float
	begin
	  x.to_s.to_int
	  t = "int"
	rescue
	  t = "float"
	end
      rescue
	t = "string"
      end
  end

  def checkall ar
    ar.each do |x|
    t = c(x)
    print t, " ", x, "\n"
    end
  end

  ar =  []
  ar << "abc"
  ar << "123"
  ar << "1.23"
  ar << "1.23e+4"
  ar << ".123"
  ar << "1e2"
  checkall ar
end

    ======================================================================
	Fringe
    ______________________________________________________________________

	[ruby-list:14890] Object-Oriented Software Construction (2nd edition)

	Akira ENDO (aka FAQ editor) might do double-click; He has received 
	two same books from amazon.com. 

	# By the way, one of Gotoken's friends received three same books from
	# amazon.com, one day. He might do triple-click. Be careful :-)

	The book is Bertrand Meyer's `Object-Oriented Software Construction 
	(2nd edition)'. Akira called somebody who wants that book and lives
	near his hometown.  Mokoto asked how good the book is (but he lives
	in Massachusetts). Yoshifumi and Matz have good word for the
	1st edition of this book. Indeed, Matz sometimes confesses that he 
	was given a shock by this book about ten years ago. He also give
	a proviso that Eiffel is not `the main current' nor `a orthodox' of
	OOPL. Of course, the value of Mayer's book is not change. It's great. 
        I think so.  But 2nd ed. is too thick, about 1200 pages!
    ______________________________________________________________________

	[ruby-list:15064] Hako iri Musume in Ruby/TK

	Masatoshi SEKI makes us merry by his implementation of a traditional 
	Japanese toy `Hako iri Musume'. I should explain what that is. 

	`Hako iri Musume' means `daughter(Musume) in(iri) a box(Hako)'. 
	In ancient Japan (and now?), a daughter is cherished very very much. 
	It was not easy to out for her because her family hampted (they might
	worry she would be abducted?). So, such a chetished girl is expressed 
	figuratively `Hako iri Musume'. The subject of this game is to help 
	a marchant's daughter out. 

	The goal is take her (the biggest piece) to the opposite position 
	(see below). Enjoy! # No fanfare will be played when you succeed.

	+------+-------------+------+        +---------------------------+
	|      |             |      |	     |                       ?   |
	|      |             |      |	     |              ?            |
	|Father|   Daughter  |Mother|	     |    ?                      |
	|      |             |      |	     |         ?       ?         |
	|      |             |      |	     |                      ?    |
	+------+------+------+------+	     |           ?               |
	|      |      |      |      |	     |    ?                      |
	| boy  | boy  | boy  | boy  |  ===>  |                    ?      |
	+------+------+------+------+	     |      +-------------+   ?  |
	|      |             |      |	     |      |             |      |
	|      |  manager    |      |        |      |             |      |
	|serv- +-------------+serv- |	     |   ?  |   Daughter  |      |
	|   ant|             |   ant|	     |      |             |      |
	|      |             |      |        |      |             |      |
	+------+-------------+------+	     +------+-------------+------+


# I (gotoken) replaced Japanese characters by ASCII characters. 
require 'tk'

class House
  def initialize(parent=nil, unit=32)
    @w = 4
    @h = 5
    @unit_size = unit
    @widget = TkFrame.new(parent,
			  'width' => @unit_size * @w,
			  'height' => @unit_size * @h).pack
    @chips = []
  end
  attr :widget
  attr :unit_size
  attr :chips

  def enter(chip)
    @chips.push chip
  end

  def wall
    hash = {}
    (-1..@w).each do |i|
      hash[[i, -1]] = true
      hash[[i, @h]] = true
    end
    (-1..@h).each do |i|
      hash[[-1, i]] = true
      hash[[@w, i]] = true
    end
    hash
  end

  def move?(chip, dx, dy)
    field = self.wall
    @chips.each do |c|
      unless c == chip
	c.area.each do |a|
	  field[a] = chip
	end
      end
    end

    chip.area(dx, dy).each do |a|
      return false if field[a]
    end
    return true
  end
end

$house = house = House.new(nil, 64)

class Chip
  def initialize(house, name, x, y, w=1, h=1)
    @name = name
    @w = w
    @h = h
    @widget = TkLabel.new(house.widget,
			  'text' => name,
			  'relief' => 'raised')
    @house = house
    @unit = @house.unit_size
    moveto(x, y)
    @house = house.enter(self)
    @widget.bind('1', proc{|e| do_press e.x, e.y})
    @widget.bind('B1-Motion', proc{|x, y| do_motion x, y}, "%x %y")
    @widget.bind('ButtonRelease-1', 
		 proc{|x, y| do_release x, y}, "%x %y")
  end
  attr :name

  def area(dx=0, dy=0)
    v = []
    for i in (1..@h)
      for j in (1..@w)
	v.push([dx + @x + j - 1, dy + @y + i - 1])
      end
    end
    v
  end

  def moveto(x, y)
    @x = x
    @y = y
    @widget.place('x' => @unit * x,
		  'y' => @unit * y,
		  'width' => @unit * @w,
		  'height' => @unit * @h)
  end

  def move(dx, dy)
    x = @x + dx
    y = @y + dy
    moveto(x, y)
  end
  
  def do_press(x, y)
  end

  def do_motion(x, y)
    if x >= @unit * @w
      dx = 1
    elsif x < 0
      dx = -1
    else
      dx = 0
    end

    if y >= @unit * @h
      dy = 1
    elsif y < 0
      dy = -1
    else
      dy = 0
    end

    if (dx != 0)
      dy = 0
    end

    return if (dx == 0) and (dy == 0)

    try_move(dx, dy)
  end

  def do_release(x, y)
  end
  
  def try_move(dx, dy)
    if $house.move?(self, dx, dy)
      move(dx, dy)
    end
  end
end

she = Chip.new(house, 'Daughter', 1, 0, 2, 2)
father = Chip.new(house, "Father", 0, 0, 1, 2)
mother = Chip.new(house, "Mother", 3, 0, 1, 2)
kozou = []
(0..3).each do |i|
  kozou.push Chip.new(house, "boy", i, 2)
end
genan = []
(0..1).each do |i|
  genan.push Chip.new(house, "servant", i * 3, 3, 1, 2)
end
bantou = Chip.new(house, "manager", 1, 3, 2, 1)

Tk.mainloop

    ======================================================================

-- gotoken

PS

I wached Star Wars Episode I. I was very surprised because Jedi knights 
often did OZIGI (__).  They must be samurai. Sith? they are ninja. 

By the way, (__) stands for a downcasting face: underscores for closed eyes. 
We use also (__;; in Japan. This face is covered (cold) sweats and means 
that she is expressing apology with all her might. 
e.g. My apology for long suspend of FromJapan (__;;;;;;;;;;;;