refactor while statement

lib/typed/compiler.rb

@@ -3,9 +3,10 @@ require_relative "tree"
 module Typed
 
   CompilerModules = [ "assignment" , "basic_values" , "call_site", "class_field" ,
-                       "class_statement" , "collections" , "field_def" , "field_access",
-                       "function_statement" , "if_statement" , "name_expression" ,
-                       "operator_expression" , "return_statement", "statement_list"]
+                      "class_statement" , "collections" , "field_def" , "field_access",
+                      "function_statement" , "if_statement" , "name_expression" ,
+                      "operator_expression" , "return_statement", "statement_list",
+                      "while_statement"]
 
   CompilerModules.each do |mod|
     require_relative "compiler/" + mod
@@ -190,5 +191,3 @@ module Typed
     end
   end
 end
-
-require_relative "compiler/while_statement"

lib/typed/compiler/if_statement.rb

@@ -7,17 +7,17 @@ module Typed
     def on_IfStatement( statement )
 #      branch_type , condition , if_true , if_false = *statement
 
-      true_block = compile_condition( statement )
-      merge = compile_false( statement )
+      true_block = compile_if_condition( statement )
+      merge = compile_if_false( statement )
       add_code true_block
-      compile_true(statement)
+      compile_if_true(statement)
       add_code merge
       nil # statements don't return anything
     end
 
     private
 
-    def compile_condition( statement )
+    def compile_if_condition( statement )
       reset_regs
       process(statement.condition)
       branch_class = Object.const_get "Register::Is#{statement.branch_type.capitalize}"
@@ -25,12 +25,12 @@ module Typed
       add_code branch_class.new( statement.condition , true_block )
       return true_block
     end
-    def compile_true( statement )
+    def compile_if_true( statement )
       reset_regs
       process(statement.if_true)
     end
 
-    def compile_false( statement )
+    def compile_if_false( statement )
       reset_regs
       process(statement.if_false) if statement.if_false.statements
       merge = Register::Label.new(statement , "if_merge")

lib/typed/compiler/while_statement.rb

@@ -1,22 +1,17 @@
 module Typed
-  Compiler.class_eval do
+  module WhileStatement
 
     def on_WhileStatement statement
-      #puts statement.inspect
       #branch_type , condition , statements = *statement
 
-      condition_label = Register::Label.new(statement.condition , "condition_label")
-      # unconditionally branch to the condition upon entering the loop
-      add_code Register::Branch.new(statement.condition,condition_label)
+      condition_label = compile_while_preamble( statement )  #jump there
 
-      add_code  start = Register::Label.new(statement , "while_start" )
-      reset_regs
-      process(statement.statements)
+      start = compile_while_body( statement )
 
       # This is where the loop starts, though in subsequent iterations it's in the middle
       add_code condition_label
-      reset_regs
-      process(statement.condition)
+
+      compile_while_condition( statement )
 
       branch_class = Object.const_get "Register::Is#{statement.branch_type.capitalize}"
       # this is where the while ends and both branches meet
@@ -24,5 +19,24 @@ module Typed
 
       nil # statements don't return anything
     end
+    private
+
+    def compile_while_preamble( statement )
+      condition_label = Register::Label.new(statement.condition , "condition_label")
+      # unconditionally branch to the condition upon entering the loop
+      add_code Register::Branch.new(statement.condition , condition_label)
+      condition_label
+    end
+    def compile_while_body( statement )
+      start = Register::Label.new(statement , "while_start" )
+      add_code start
+      reset_regs
+      process(statement.statements)
+      start
+    end
+    def compile_while_condition( statement )
+      reset_regs
+      process(statement.condition)
+    end
   end
 end