class
	{
	New(fileName)
	{
	.tokenizing = Tokenizing(fileName)
	.space = ""
	.result = ""
	}

	addSpace()
	{
	.space $= "    "
	}

	subSpace()
	{
	.space = .space.Substr(4)
	}

	writeClass()
	{
	.tokenizing.Advance()
	.result $= "\n" $ .space $ "<class>"
	.addSpace()

	.writeTag("class","keyword")
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "identifier")
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")// write {

	.tokenizing.Advance()
	while(.tokenizer.Token() is "static" or .tokenizer.Token() is "field"){
		.writeClassVarDec()//ToDo
		.tokenizing.Advance()
			 }

	while(.tokenizer.Token() is "constructor"
		or .tokenizer.Token() is "function"
			or.tokenizer.Token() is "method"){
		.writeSubRoutine()//ToDo
		.tokenizing.Advance()
			 }
	.writeTag(.tokenizer.Token(), "symbol")// write }
	.subSpace()
	.result $= "\n" $ .space $ "</class>"
	}

	writeClassVarDec()
	{
		.result $= "\n" $ .space $ "<classVarDec>"
		.addSpace()

		.writeTag(.tokenizer.Token(),"keyword")// var

		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(),"type")

		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(),"identifier")

		.tokenizing.Advance()
		while(.tokenizer.Token() is "," )
			{
			.writeTag(.tokenizer.Token(),"symbol")
			.tokenizing.Advance()
			.writeTag(.tokenizer.Token(),"identifier")
			.tokenizing.Advance()
			}

		.writeTag(.tokenizer.Token(),"symbol") // write ;
		.subSpace()
		.result $= "\n" $ .space $ "</classVarDec>"
	}

	writeTag(terminal,type)
	{
	.result $= "\n" $ .space $ "<" $ type $ ">" $ terminal $ "</" $ type $ ">"
	}

	writeSubRoutine()
	{
	.result $= "\n" $ .space $ "<subroutineDec>"
	.addSpace()
	.writeTag(.tokenizer.Token(),"keyword")//ect. method
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(),"keyword")//ect. void,int
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(),"identifier")
	.writeTag(.tokenizer.Token(),"symbol") // write (
	.writeParameterList()
	.writeTag(.tokenizer.Token(),"symbol") // write )
	.writeSubroutineBody()
	.subSpace()
	.result $= "\n" $ .space $ "</subroutineDec>"
	}
	writeParameterList()
	{
	.result $= "\n" $ .space $ "<parameterList>"
	.addSpace()
	.tokenizing.Advance()
	if(.tokenizer.Token() isnt ")")
		{
		.writeTag(.tokenizer.Token(),"keyword")//type
		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(),"identifier")
		.tokenizing.Advance()
		while(.tokenizer.Token() is "," )
			{
			.writeTag(.tokenizer.Token(),"symbol")
			.tokenizing.Advance()
			.writeTag(.tokenizer.Token(),"keyword")//type
			.tokenizing.Advance()
			.writeTag(.tokenizer.Token(),"identifier")
			.tokenizing.Advance()
			}
		}
	.subSpace()
	.result $= "\n" $ .space $ "</parameterList>"
	}
	writeSubroutineBody()
	{
	.result $= "\n" $ .space $ "<subroutineBody>"
	.addSpace()
	.writeTag(.tokenizer.Token(), "symbol")//write {
	.tokenizing.Advance()

	while(.tokenizer.Token() is "var" )
		{
		.writeVarDec()
		.tokenizing.Advance()
		}

	.writeStatements()
	.writeTag(.tokenizer.Token(), "symbol")//write }
	.subSpace()
	.result $= "\n" $ .space $ "</subroutineBody>"
	}

	writeVarDec()
	{
	.result $= "\n" $ .space $ "<varDec>"
	.addSpace()
	.writeTag(.tokenizer.Token(),"keyword")//var
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(),"keyword")//type
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(),"identifier")
	.tokenizing.Advance()
	while(.tokenizer.Token() is ",")
		{
		.writeTag(.tokenizer.Token(), "symbol")//write ,
		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(),"keyword")//type
		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(),"identifier")
		.tokenizing.Advance()
		}

	.writeTag(.tokenizer.Token(), "symbol")//write ;

	.subSpace()
	.result $= "\n" $ .space $ "</varDec>"
	}

	.writeStatements()
	{
	.result $= "\n" $ .space $ "<statements>"
	.addSpace()

	while(.isKeyword(.tokenizer.Token()))
		{
		switch .tokenizer.Token()
			{
			case "if"
				.writeIf()
				.tokenizing.Advance()
			case "let"
				.writeLet()
				.tokenizing.Advance()
			case "while"
				.writeWhile()
				.tokenizing.Advance()
			case "do"
				.writeDo()
				.tokenizing.Advance()
			case "return"
				.writeReturn()
				.tokenizing.Advance()
			}
		}

	.subSpace()
	.result $= "\n" $ .space $ "</statements>"
	}

	writeLet()
	{
	.result $= "\n" $ .space $ "<letStatement>"
	.addSpace()

	.writeTag(.tokenizer.Token(),"keyword")//let
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(),"identifier")
	.tokenizing.Advance()

	if .tokenizer.Token() is "["
		{
		.writeTag(.tokenizer.Token(), "symbol")//write [
		.tokenizing.Advance()
		.writeExpression()//ToDo
		.writeTag(.tokenizer.Token(), "symbol")//write ]
		.tokenizing.Advance()
		}
	.writeTag(.tokenizer.Token(), "symbol")//write =
	.tokenizing.Advance()
	.writeExpression()
	.writeTag(.tokenizer.Token(), "symbol")//write ;

	.subSpace()
	.result $= "\n" $ .space $ "</letStatement>"
	}

	writeIf()
	{
	.result $= "\n" $ .space $ "<ifStatement>"
	.addSpace()

	.writeTag(.tokenizer.Token(),"keyword")//if
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")//write (
	.tokenizing.Advance()
	.writeExpression()
	.writeTag(.tokenizer.Token(), "symbol")//write )
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")//write {
	.tokenizing.Advance()
	.writeStatements()
	.writeTag(.tokenizer.Token(), "symbol")//write }

	.tokenizing.Advance()
	if(.tokenizer.Token() is "else")
		{
		.writeTag(.tokenizer.Token(),"keyword")//else
		.tokenizing.Advance()
		.writeTag(.tokenizer.Token(), "symbol")//write {
		.tokenizing.Advance()
		.writeStatements()
		.writeTag(.tokenizer.Token(), "symbol")//write }
		.tokenizing.Advance()
		}
	.subSpace()
	.result $= "\n" $ .space $ "</ifStatement>"
	}

	writeWhile()
	{
	.result $= "\n" $ .space $ "<whileStatement>"
	.addSpace()

	.writeTag(.tokenizer.Token(),"keyword")//while
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")//write (
	.tokenizing.Advance()
	.writeExpression()
	.writeTag(.tokenizer.Token(), "symbol")//write )
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")//write {
	.tokenizing.Advance()
	.writeStatements()
	.writeTag(.tokenizer.Token(), "symbol")//write }

	.subSpace()
	.result $= "\n" $ .space $ "</whileStatement>"
	}

	writeDo()
	{
	.result $= "\n" $ .space $ "<doStatement>"
	.addSpace()

	.writeTag(.tokenizer.Token(),"keyword")//do
	.tokenizing.Advance()
	.writeTag(.tokenizer.Token(), "symbol")//write {
	.tokenizing.Advance()
	.writeStatements()

	.subSpace()
	.result $= "\n" $ .space $ "</doStatement>"
	}

	isKeyword(str)
	{
	keywords = #["let","if","do","while","return"]
	for key in keywords
		if str is key
			return true
	return false
	}


}