SlotLanguage reborn in the Machine

Just added the compiler, that can parse Slot directly into SlotMachine code (no language layer in between)
Still unclear wheather the Maker is a thing, but since it was in the Language layer i did not remove it (yet)
Otherwise just the compiler and all the tests, moved from the slot_language.

lib/slot_machine/macro_maker.rb

@@ -0,0 +1,30 @@
+module SlotMachine
+
+  class MacroMaker
+    # a list of instructions
+
+    attr_reader :instructions
+
+    # load slot code from a file, in a subdir code/ + filename
+    # use load_string to compile the content
+    def self.load_file(relative_name)
+      path = File.expand_path(  "../code/#{relative_name}" , __FILE__)
+      load_string( File.read(path))
+    end
+
+    # compile the given SlotLanguage source
+    # the compiler returns an array of Makers which a new MacroMaker
+    # instance stores
+    # return the MacroMaker that represents the source
+    def self.load_string(source_code)
+      MacroMaker.new( SlotCompiler.compile(source_code) )
+    end
+
+    # must initialize with an array of Makers, which is stored
+    def initialize( instructions )
+      @instructions = instructions
+      raise "undefined source #{instructions}" unless instructions.is_a?(Instruction)
+    end
+
+  end
+end

lib/slot_machine/slot_compiler.rb

@@ -0,0 +1,134 @@
+require "parser/current"
+require "ast"
+
+module SlotMachine
+  class SlotCompiler < AST::Processor
+    DEBUG = false
+
+    # conditionals supported, currently only equal
+    def self.checks
+      [:==]
+    end
+
+    def self.compile(input)
+      ast = Parser::CurrentRuby.parse( input )
+      self.new.process(ast)
+    end
+    attr_reader :labels
+    def initialize
+      @labels = {}
+    end
+
+    def not_implemented(node)
+      raise "Not implemented #{node.type}"
+    end
+    # default to error, so non implemented stuff shows early
+    def handler_missing(node)
+      not_implemented(node)
+    end
+    def process_all(exp)
+      arr = super(exp)
+      head = arr.shift
+      until( arr.empty?)
+        head << arr.shift
+      end
+      head
+    end
+    def on_send(statement)
+      kids = statement.children.dup
+      receiver = kids.shift
+      name = kids.shift
+      return label(name) if(name.to_s.end_with?("_label"))
+      return goto(name,kids) if(name == :goto)
+      return check(name,receiver, kids) if SlotCompiler.checks.include?(name)
+      return assign(receiver, name , kids) if(name.to_s.end_with?("="))
+      puts "Send: #{statement} " if DEBUG
+      var = SlottedMessage.new( [name] )
+      if(receiver)
+        puts "receiver at #{name} #{receiver}" if DEBUG
+        prev = process(receiver)
+        prev.set_next(var.slots)
+        prev
+      else
+        var
+      end
+    end
+    def on_lvar(lvar)
+      puts "lvar #{lvar}" if DEBUG
+      SlottedMessage.new( [lvar.children.first] )
+    end
+    def on_lvasgn( expression)
+      puts "i/lvasgn #{expression}" if DEBUG
+      var = var_for(expression.children[0])
+      value = process(expression.children[1])
+      SlotLoad.new(expression.to_s,var , value)
+    end
+    alias :on_ivasgn :on_lvasgn
+
+    def on_if(expression)
+      puts "if #{expression}" if DEBUG
+      condition = process(expression.children[0])
+      jump = process(expression.children[1])
+      condition.set_label( jump.label )
+      condition
+    end
+    def on_begin(exp)
+      if( exp.children.length == 1)
+        process(exp.first)
+      else
+        process_all(exp)
+      end
+    end
+    def on_ivar(expression)
+      puts "ivar #{expression}" if DEBUG
+      var_for(expression.children.first)
+    end
+
+    private
+
+    def var_for( name )
+      name = name.to_s
+      if(name[0] == "@")
+        var = name.to_s[1 .. -1].to_sym
+        SlottedMessage.new([:receiver , var])
+      else
+        SlottedMessage.new([:receiver , name])
+      end
+    end
+    def label(name)
+      raise "no label #{name}" unless(name.to_s.end_with?("_label"))
+      if @labels.has_key?(name)
+        return @labels[name]
+      else
+        @labels[name] = SlotMachine::Label.new(name.to_s , name)
+      end
+    end
+    def goto(name , args)
+      # error handling would not hurt
+      puts "goto #{name} , #{args}" if DEBUG
+      label = process(args.first)
+      Jump.new( label )
+    end
+    def check(name , receiver , kids)
+      raise "Familiy too large #{kids}" if kids.length > 1
+      puts   "Kids " + kids.to_s if DEBUG
+      right = process(kids.first)
+      case name
+      when :==
+        return SameCheck.new(process(receiver) , right , Label.new("none", :dummy))
+      else
+        raise "Only ==, not #{name}" unless name == :==
+      end
+    end
+
+    def assign(receiver , name , kids)
+      receiver = process(receiver)
+      puts "Assign #{name} , #{receiver}" if DEBUG
+      raise "Only one arg #{kids}" unless kids.length == 1
+      right = process kids.shift
+      name = name.to_s[0...-1].to_sym
+      receiver.set_next(Slot.new(name))
+      SlotLoad.new("#{receiver} = #{name}",receiver,right)
+    end
+  end
+end

lib/slot_machine/slot_machine.rb

@@ -23,3 +23,5 @@ require_relative "callable_compiler"
 require_relative "method_compiler"
 require_relative "block_compiler"
 require_relative "macro/macro"
+require_relative "slot_compiler"
+require_relative "macro_maker"

lib/slot_machine/slotted.rb

@@ -21,7 +21,7 @@ module SlotMachine
 
     def initialize( slots = nil )
       return unless slots
-      raise "stopped" unless slots.is_a?(Array)
+      raise "stopped #{slots.class}" unless slots.is_a?(Array)
       first = slots.shift
       raise "ended" unless first
       @slots = Slot.new(first)