metaclass is back

this time with a real purpose and implementation as the intermediary
As the interface to the layout and for replacing an edited layout
This commit is contained in:
Torsten Ruger 2015-11-07 00:11:56 +02:00
parent ebcc15d314
commit 204200b92a
5 changed files with 73 additions and 19 deletions

View File

@ -7,6 +7,7 @@ require "parfait/list"
require "parfait/word"
require "parfait/binary_code"
require "parfait/method"
require "parfait/meta_class"
require "parfait/variable"
require "parfait/dictionary"
require "parfait/layout"

View File

@ -96,11 +96,5 @@ module Parfait
nil # stop resolve recursing up metaclasses
end
def create_instance_method method_name , arguments
raise "create_instance_method #{method_name}.#{method_name.class}" unless method_name.is_a?(Symbol)
#puts "Self: #{self.class} clazz: #{clazz.name}"
add_instance_method Method.new( self , method_name , arguments )
end
end
end

68
lib/parfait/meta_class.rb Normal file
View File

@ -0,0 +1,68 @@
module Parfait
# class that acts like a class, but is really the object
# described in the ruby language book as the eigenclass, what you get with
# class MyClass
# class << self <--- this is called the eigenclass, or metaclass, and really is just
# .... the class object but gives us the ability to use the
# syntax as if it were a class
# While the "real" metaclass is the layout, we need to honor the constancy of the layout
# So the layout needs to be copied and replaced anytime it is edited.
# And then changed in the original object, and thus we need this level of indirection
# Basically we implement the Behaviour protocol, by forwarding to the layout
class MetaClass < Object
include Logging
attribute :object
def initialize(object)
super()
self.object = object
end
def name
self.object.get_layout.name
end
# first part of the protocol is read, just forward to self.object.layout
def methods
self.object.get_layout.methods
end
def method_names
self.object.get_layout.method_names
end
def get_instance_method fname
self.object.get_layout.get_instance_method fname
end
def resolve_method m_name
self.object.get_layout.resolve_method m_name
end
# the modifying part creates a new layout
# forwards the action and replaces the layout
def add_instance_method method
layout = self.object.get_layout.dup
ret = layout.add_instance_method(method)
self.object.set_layout layout
ret
end
def remove_instance_method method_name
layout = self.object.get_layout.dup
ret = layout.remove_instance_method(method_name)
self.object.set_layout layout
ret
end
def create_instance_method method_name , arguments
raise "create_instance_method #{method_name}.#{method_name.class}" unless method_name.is_a?(Symbol)
log.debug "Add_method: #{method_name} clazz: #{self.name}"
add_instance_method Method.new( self , method_name , arguments )
end
end
end

View File

@ -114,15 +114,14 @@ module Register
def layout_names
{ :Word => {:char_length => :Integer} ,
:List => {:indexed_length => :Integer} ,
# Assumtion is that name is the last of message
:Message => { :next_message => :Message, :receiver => :Object, :frame => :Frame ,
:return_address => :Integer, :return_value => :Integer,
:caller => :Message , :name => :Word , :indexed_length => :Integer },
:MetaClass => {:me => :Class},
:MetaClass => {:object => :Object},
:Integer => {},
:Object => {},
:Kernel => {}, #fix, kernel is a class, but should be a module
:BinaryCode => {},
:BinaryCode => {:name => :Word},
:Space => {:classes => :Dictionary , :first_message => :Message},
:Frame => {:next_frame => :Frame, :indexed_length => :Integer},
:Layout => {:object_class => :Class, :instance_methods => :List , :indexed_length => :Integer} ,

View File

@ -20,17 +20,9 @@ class TestMeta < MiniTest::Test
end
def test_new_methods
assert_equal @try.method_names.class, @try.instance_methods.class
assert_equal @try.method_names.get_length , @try.instance_methods.get_length
assert_equal 0 , @try.method_names.get_length
end
def test_init_methods
assert_equal 3 , @try.get_layout.variable_index(:instance_methods)
@try.instance_methods = Parfait::List.new
assert_equal @try.instance_methods , @try.internal_object_get(3)
assert @try.instance_methods
end
def test_create_method
@try.create_instance_method :bar, Register.new_list( [ Parfait::Variable.new(:Integer , :bar )])
assert_equal ":bar" , @try.method_names.inspect
@ -38,7 +30,7 @@ class TestMeta < MiniTest::Test
def test_add_method
foo = foo_method
assert_equal foo , @try.add_instance_method(foo)
assert_equal 1 , @try.instance_methods.get_length
assert_equal 1 , @try.method_names.get_length
assert_equal ":foo" , @try.method_names.inspect
end
def test_remove_method