diff --git a/assets/parser.d.erb b/assets/parser.d.erb
index c0f45bf..87e1f18 100644
--- a/assets/parser.d.erb
+++ b/assets/parser.d.erb
@@ -1,5 +1,5 @@
-<% if grammar.modulename %>
-module <%= grammar.modulename %>;
+<% if @grammar.modulename %>
+module <%= @grammar.modulename %>;
 
 <% end %>
 class <%= classname %>
diff --git a/lib/imbecile.rb b/lib/imbecile.rb
index 99c56f0..b6583cc 100644
--- a/lib/imbecile.rb
+++ b/lib/imbecile.rb
@@ -2,6 +2,7 @@ require "erb"
 require "set"
 require_relative "imbecile/cli"
 require_relative "imbecile/code_point_range"
+require_relative "imbecile/generator"
 require_relative "imbecile/grammar"
 require_relative "imbecile/grammar/rule"
 require_relative "imbecile/grammar/token"
@@ -24,22 +25,12 @@ module Imbecile
     def run(input_file, output_file)
       begin
         grammar = Grammar.new(File.read(input_file))
-        # Build NFA from each token expression.
-        grammar.tokens.each do |token|
-          puts token.nfa
-        end
-        lexer_dfa = LexerDFA.new(grammar.tokens)
-        puts lexer_dfa
+        generator = Generator.new(grammar)
+        generator.generate(output_file)
       rescue Error => e
         $stderr.puts e.message
         return 2
       end
-      classname = grammar.classname || output_file.sub(%r{[^a-zA-Z0-9].*}, "").capitalize
-      erb = ERB.new(File.read(File.join(File.dirname(File.expand_path(__FILE__)), "../assets/parser.d.erb")), nil, "<>")
-      result = erb.result(binding.clone)
-      File.open(output_file, "wb") do |fh|
-        fh.write(result)
-      end
       return 0
     end
 
diff --git a/lib/imbecile/generator.rb b/lib/imbecile/generator.rb
new file mode 100644
index 0000000..fa9ec9f
--- /dev/null
+++ b/lib/imbecile/generator.rb
@@ -0,0 +1,22 @@
+module Imbecile
+
+  # Class to generate the parser generator source.
+  class Generator
+
+    def initialize(grammar)
+      @grammar = grammar
+    end
+
+    def generate(output_file)
+      lexer_dfa = LexerDFA.new(@grammar.tokens)
+      classname = @grammar.classname || output_file.sub(%r{[^a-zA-Z0-9].*}, "").capitalize
+      erb = ERB.new(File.read(File.join(File.dirname(File.expand_path(__FILE__)), "../../assets/parser.d.erb")), nil, "<>")
+      result = erb.result(binding.clone)
+      File.open(output_file, "wb") do |fh|
+        fh.write(result)
+      end
+    end
+
+  end
+
+end