refactor if_statement

lib/typed/compiler/if_statement.rb

@@ -1,35 +1,41 @@
 module Typed
-  Compiler.class_eval do
+  module IfStatement
 
     # an if evaluates the condition and jumps to the true block if true
     # so the else block is automatically after that.
     # But then the else needs to jump over the true block unconditionally.
-    def on_IfStatement statement
+    def on_IfStatement( statement )
 #      branch_type , condition , if_true , if_false = *statement
-#      condition = condition.first
 
+      true_block = compile_condition( statement )
+      merge = compile_false( statement )
+      add_code true_block
+      compile_true(statement)
+      add_code merge
+      nil # statements don't return anything
+    end
+
+    private
+
+    def compile_condition( statement )
       reset_regs
       process(statement.condition)
-
       branch_class = Object.const_get "Register::Is#{statement.branch_type.capitalize}"
       true_block = Register::Label.new(statement, "if_true")
       add_code branch_class.new( statement.condition , true_block )
+      return true_block
+    end
+    def compile_true( statement )
+      reset_regs
+      process(statement.if_true)
+    end
 
-      # compile the false block
+    def compile_false( statement )
       reset_regs
       process(statement.if_false) if statement.if_false.statements
       merge = Register::Label.new(statement , "if_merge")
       add_code Register::Branch.new(statement.if_false, merge )
-
-      # compile the true block
-      add_code true_block
-      reset_regs
-      process(statement.if_true)
-
-      #puts "compiled if: end"
-      add_code merge
-
-      nil # statements don't return anything
+      merge
     end
   end
 end