From: Eric Mahurin <eric_mahurin@...>
Date: 2005-05-09T06:27:37+09:00
Subject: [ANN] reference 0.5 (was Re: object reference handle (like perl's reference to scalar))

I just released the code that has already been discussed here
in gem form.  Assuming you already have rubygems, you should be
able to do "gem install reference" and then this in your ruby
code:

require 'rubygems'
require_gem 'reference'

Here are the examples I have in the embedded docs to give you
an idea of all the ways you can make and use references:

 a = ("a".."h").to_a       # ["a", "b", "c", "d", "e", "f",
"g", "h"]
 b = a                     # b and a have the same object
 p = ref{:a}               # reference to the variable :a
 q = a.ref                 # reference to the object in a
 r = ref{"a[4]"}           # reference to the assignable
expression a[4]
 s = a.ref[4]              # reference to the [4] attribute of
a
 t = a.ref.[](4)           # same
 u = a.ref(:"[]",:"[]=",4) # same except set/get method names
are explicit
 v = a.ref([:"[]",4],[:"[]=",4]) # same except arguments are
explicit
 p[]                       # ["a", "b", "c", "d", "e", "f",
"g", "h"]
 p[] = (0..7).to_a         # [0, 1, 2, 3, 4, 5, 6, 7]
 a                         # [0, 1, 2, 3, 4, 5, 6, 7]
 b                         # ["a", "b", "c", "d", "e", "f",
"g", "h"]
 q[]                       # ["a", "b", "c", "d", "e", "f",
"g", "h"]
 q[] = (-7..0).to_a        # [-7, -6, -5, -4, -3, -2, -1, 0]
 a                         # [0, 1, 2, 3, 4, 5, 6, 7]
 b                         # [-7, -6, -5, -4, -3, -2, -1, 0]
 r[]                       # 4
 r[] = "r"                 # "r"
 a                         # [0, 1, 2, 3, "r", 5, 6, 7]
 b                         # [-7, -6, -5, -4, -3, -2, -1, 0]
 # extra arg is slice length
 s[2]                      # [-3, -2]
 s[2] = ["s"]              # ["s"]
 a                         # [0, 1, 2, 3, "r", 5, 6, 7]
 b                         # [-7, -6, -5, -4, "s", -1, 0]
 t[]                       # "s"
 t[] = "t"                 # "t"
 a                         # [0, 1, 2, 3, "r", 5, 6, 7]
 b                         # [-7, -6, -5, -4, "t", -1, 0]
 u[]                       # "t"
 u[] = "t"                 # "u"
 a                         # [0, 1, 2, 3, "r", 5, 6, 7]
 b                         # [-7, -6, -5, -4, "u", -1, 0]
 v[]                       # "t"
 v[] = "t"                 # "v"
 a                         # [0, 1, 2, 3, "r", 5, 6, 7]
 b                         # [-7, -6, -5, -4, "v", -1, 0]

 # multiple ways to make a reference to lines in stdin/stdout
 lineref = Reference.new(method(:gets),method(:puts))
 lineref = Reference.new(proc{gets},proc{|v|puts(v)})
 line = lineref[] # line = gets
 lineref[]="hello world!" # puts("hello world!")



		
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