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|
# TITLE:
#
# State
#
# SUMMARY:
#
#
#
# AUTHORS:
#
# - Thomas Sawyer
# = State
#
class State < Hash
#def initialize(object)
#end
def data_represents( klass )
@data_represents = klass
end
def data_represents?( klass )
@data_represents == klass
end
def to_object( klass=nil )
#raise unless @data_represention
obj = (klass||@data_represents).allocate
obj.from_data( self )
obj
end
def to_data
dup
end
def from_data(state)
replace(state)
end
end
#
module Kernel
# Create a hash representation of an object.
def to_data( deep=false )
#return self if Hash === self.class #object_class
data = {}
data.data_represents(self.class)
instance_variables.each do |iv|
name = iv[1..-1].to_sym # removes @
value = instance_variable_get(iv)
value = value.to_data if deep
data[name] = value
end
data
end
# Restore objects state from a hash representation of the object.
def from_data(snap)
#instance_variables.each { |iv| instance_variable_set(iv, snap[iv]) }
snap.each { |iv, value| instance_variable_set("@#{iv}", value) }
self
end
end
class Array
def to_data ; dup ; end
end
class String
def to_data() dup end
def from_data(snap) replace(snap) end
end
class Struct
def to_data
snap = Hash.new
each_pair {|k,v| snap[k] = v}
snap
end
def from_data(snap)
snap.each_pair {|k,v| send(k.to_s + "=", v)}
end
end
=begin test
require 'test/unit'
class TestToData < Test::Unit::TestCase
class X
attr_accessor :a, :b, :c
def initialize(a, b, c)
@a, @b, @c = a, b, c
end
def ==( other )
return false if @a != other.a
return false if @b != other.b
return false if @c != other.c
true
end
end
def test_001
x = X.new( 1, 2, 3 )
assert_equal( { :a=>1, :b=>2, :c=>3 }, x.to_data )
end
def test_002
x = X.new( 1, 2, [:a,:b] )
assert_equal( { :a=>1, :b=>2, :c=>[:a,:b] }, x.to_data )
end
def test_003
x = X.new( 1, 2, 3 )
d = x.to_data
x.a = 3
assert_equal( 3, x.a )
x.from_data(d)
assert_equal( 1, x.a )
end
def test_004
x = X.new( 1, 2, 3 )
d = x.to_data
y = d.to_object
assert_equal( x, y )
end
end
=end
|
