import ast
import compiler

def process(node):
  forCondition = ast.nextLabel()
  afterFor = ast.nextLabel()
  iterator = ast.nextPRegister()
  list = ast.nextPRegister()
  iteratorVariable = ast.nextPRegister()
  
  ast.outputInBlock(".include \"iterator.pasm\"")
  ast.outputInBlock("%s = %s" % ( list, ast.evaluate( node.list ) ) )
  ast.outputInBlock("new %s, .Iterator, %s" % ( iterator, list ) )
  ast.outputInBlock("set %s, .ITERATE_FROM_START" % ( iterator ) )
  ast.outputLabel( forCondition )
  ast.outputInBlock( "unless %s, %s" % ( iterator, afterFor ) )
 
  ast.outputInBlock("shift %s, %s" % ( iteratorVariable, iterator ) )
  ast.outputInBlock("%s = %s" % ( ast.evaluate( node.assign ), iteratorVariable ) )

  ast.evaluate( node.body )
  ast.outputInBlock( "branch %s" % ( forCondition ) )
  ast.outputLabel( afterFor )