From ce3505710a29b9697c80d67254aa1957111643a5 Mon Sep 17 00:00:00 2001
From: Torsten Ruger <torsten@villataika.fi>
Date: Tue, 5 Aug 2014 15:55:24 +0300
Subject: [PATCH] basic send

---
 lib/parfait/README.md  | 40 +++++++++++++++++++++++++++++++++++++++-
 lib/parfait/array.rb   |  2 +-
 lib/parfait/message.rb | 24 ++++++++++++++++++++++++
 lib/parfait/object.rb  |  4 ++++
 4 files changed, 68 insertions(+), 2 deletions(-)
 create mode 100644 lib/parfait/message.rb

diff --git a/lib/parfait/README.md b/lib/parfait/README.md
index 2a2f3350..1e22aeb8 100644
--- a/lib/parfait/README.md
+++ b/lib/parfait/README.md
@@ -4,4 +4,42 @@ Here we have a placeholder for things i am currently developing.
 
 Basically Parfait is the smallest amount of code needed to make a ruby-like OO system work.
 
-A work in progress that started from here : http://salama.github.io/2014/06/10/more-clarity.html
+A work in progress that started from here : http://salama.github.io/2014/06/10/more-clarity.html went on here
+http://salama.github.io/2014/07/05/layers-vs-passes.html
+
+And i finally came to the conclusion that Parfait is the ruby runtime. Aha
+
+Run - time
+
+not compile - time
+
+always mixing those up: As such it is not loaded at compile time.
+
+A step back:  the code (program) we compile runs at run - time. 
+And so does parfait. So all we have to do is compile it with the program.
+
+And thus parfait can be used at run-time.
+
+It's too simple: just slips off the mind like a fish into water.
+
+#### Example: Message send
+
+I felt a little stupid that it took me so long to notice that sending a message is very closely relateed to the
+existing ruby method Object.send
+
+Off course object.send takes symbol and the arguments and has the receiver, so all the elements of our Messaage are there.
+And the process that Object.send needs to do is exactly that: send that message, ie find the correct method according to 
+the old walk up the inheritance tree rules and dispatch it.
+
+And as all this happens at runtime, "all" we have to do is code this logic. And since it is at runtime, we can do it in ruby
+(as i said, this get's compiled and run, just like the program).
+
+But what about the infinite loop problem:
+
+There was a little step left out: Off course the method gets compiled at compile-time and so we don't just blindly dispatch:
+we catch the simple cases that we know about: layout, type instance variables and compile time known functions. Part of 
+those are some that we just don't allow to be overridden.
+
+Also what in ruby is object.send is Message.send in salama, as it is the message we are sending and which defines all the 
+data we need (not the object). The object receives, it does not send.
+
diff --git a/lib/parfait/array.rb b/lib/parfait/array.rb
index e9b5065b..8f0abef6 100644
--- a/lib/parfait/array.rb
+++ b/lib/parfait/array.rb
@@ -1,5 +1,5 @@
 # this is not a "normal" ruby file, ie it is not required by salama
-# instead it is parsed by salama to define part of the salama that runs
+# instead it is parsed by salama to define part of the program that runs
 
 class Array < BaseObject
   def initialize size
diff --git a/lib/parfait/message.rb b/lib/parfait/message.rb
new file mode 100644
index 00000000..e7b9a331
--- /dev/null
+++ b/lib/parfait/message.rb
@@ -0,0 +1,24 @@
+# this is not a "normal" ruby file, ie it is not required by salama
+# instead it is parsed by salama to define part of the program that runs
+
+class Message
+  def send
+    # Find the method for the given object (receiver) according to ruby dispatch rules:
+      # - see if the receiver object has a (singleton) method by the name
+      # - get receivers class and look for instance methods of the name
+      # - go up inheritance tree
+      # - start over with method_missing instead
+      #    -> guaranteed to end at object.method_missing 
+    method = @receiver.get_singeton_method @method_name
+    unless method
+      cl = @receiver.layout.object_class
+      method = cl.get_instance_or_super_method @method_name
+    end
+    unless method
+      message = Message.new( @receiver , :method_missing , [@method_name] + @args)
+      message.send
+    else
+      method.call
+    end
+  end
+end
diff --git a/lib/parfait/object.rb b/lib/parfait/object.rb
index 5ac0e951..879295ed 100644
--- a/lib/parfait/object.rb
+++ b/lib/parfait/object.rb
@@ -1,2 +1,6 @@
+# this is not a "normal" ruby file, ie it is not required by salama
+# instead it is parsed by salama to define part of the program that runs
+
 class Object
+
 end