A good start on the macro idea

I call it macro because it lets you insert basically arbitrary risc code into the ruby level. The way it works:
Reserve namespace X
map any X.some_call to a Mom instruction
by the name SomeCall
which must take the same args in constructor as given
And obviously produce whatever risc it wants
Hoping to rewrite builtin around this idea (with the existing Mom builtn instructions)

test/vool/test_macro_expression.rb

@@ -0,0 +1,35 @@
+require_relative "helper"
+module Mom
+  class PlusEquals < Instruction
+    attr_reader :a , :b
+    def initialize(source , arg , b)
+      super(source)
+      @a = arg
+      @b = b
+    end
+  end
+end
+
+module Vool
+  class TestMacroMom < MiniTest::Test
+    include VoolCompile
+
+    def setup
+      @compiler = compile_first_method( "X.plus_equals(arg,1)")
+      @ins = @compiler.mom_instructions.next
+    end
+
+    def test_class_compiles
+      assert_equal Mom::PlusEquals , @ins.class , @ins
+    end
+    def test_arg1
+      assert_equal  Vool::LocalVariable , @ins.a.class
+      assert_equal  :arg , @ins.a.name
+    end
+    def test_arg2
+      assert_equal  Vool::IntegerConstant , @ins.b.class
+      assert_equal  1 , @ins.b.value
+    end
+  end
+
+end