## HarveyParser.jj

options {
DEBUG_LOOKAHEAD = false;
DEBUG_PARSER = false;
}

PARSER_BEGIN(HarveyParser)
import java.io.*;
public class HarveyParser {
	public static void main(String[] args) {
		FileReader sr = null;
		try {
 			sr = new FileReader(args[0]);
		} catch (Exception e) {}

		HarveyParser p = new HarveyParser(sr);

   		try {
      		//p.Program();
			SimpleNode node = p.Program();
			// dump is the AST printer
			node.dump(">");
   		} catch (Exception e) {}

	}
}
PARSER_END(HarveyParser)

SKIP : {
<IGNORE : ["(", ")", " ", ",", "\n", "\r", "\t"]>
| <SCOMMENT : ";" (~["\n", "\r"])* ("\r" | "\n" | "\r\n")>
}

SimpleNode Program() : {} {
	{ System.out.println("program");}


	<BEGIN_PROGRAM>
	(
	try {
	 	ctrlstatement()
		| Statement()
		| FunctionDecl()
		| Error() { handleError(token); }
	}
	catch (ParseException ex) {
		handleError(ex.currentToken);
	}
	)*

	<END_PROGRAM>


{ System.out.println("end program");}
<EOF>

// jjtree stuff - jjtThis is the current AST node
{ return jjtThis; }

}

void Error() :{} {
{ System.out.println("error"); }
<ERROR>
}

void ctrlstatement() :{} {
(ifstatement() | condstatement() | dostatement())

}
void ifstatement() :{} {
<IF>
condblock()
}
void condstatement() :{} {
<COND>
(
condblock()
)+
}
void condblock() : {} {
"["
expr()
(Statement())*
"]"
}
void dostatement() :{} {

<DO>
<IDENTIFIER>
<NUMBER>
expr()
condblock()
}
void Statement() : {} {
{ System.out.println("statement"); }
"|"
(
((FunctionName() | <PRINT>) expr())
|sexpr()
)
}

void FunctionDecl() : {} {
{ System.out.println("function"); }
"["
FunctionName()
(FuncArguments())*
( Statement() )*
(FuncReturn())?
"]"
}
void expr(): {} {
(Arguments())+ | sexpr()
}
void sexpr(): {}{
(<PLUS> | <MINUS> | <STAR> | <EQUAL> | <BACKSLASH> | <GREATER_THAN> | <GREATER_EQUALS> | <LESS_THAN> | <LESS_EQUALS>)
(Arguments())
(Arguments())+
}

void FunctionName() : {} {
{ System.out.println("functionname"); }
<IDENTIFIER>
}
void FuncReturn() : {} {
{System.out.println("functionret"); }
<RETURN>
expr()
}
void FuncArguments() : {} {
{ System.out.println("func_arguments"); }
(<IDENTIFIER> | (<NUMBER>))
}
void Arguments() : {} {
{ System.out.println("arguments"); }
(<IDENTIFIER> | (<NUMBER>))
}

TOKEN : {
   <BEGIN_PROGRAM : ("<PROGRAM>")>
| <END_PROGRAM : ("</PROGRAM>")>
//reserved
|<RETURN: "return">
|<COND: "cond">
|<PRINT: "print">
|<IF: "if">
|<DO: "do">
//tokens
| <IDENTIFIER : (<LETTER> | "_") (<LETTER> | <DIGIT> | "_")*>
{ debugStream.println("IDENTIFIER token: " + matchedToken.image); }
| <STRING : ("\"") (~["\n", "\r"])* ("\"")>
{ debugStream.println("STRING token: " + matchedToken.image); }
| <NUMBER : (<INT_DECIMAL> | <INT_OCTAL> | <INT_HEXADECIMAL>)>
{ debugStream.println("NUMBER token: " + matchedToken.image); }
| <FLOATING_POINT : (<DIGIT>)+<DOT>(<FLOATFRAC>)? (<FLOATEXP>)? | <DOT><FLOATFRAC>(<FLOATEXP>)? | (<DIGIT>)+<FLOATEXP>  >
{ debugStream.println("FLOATING_POINT token: " + matchedToken.image); }
| <#FLOATFRAC : (<DIGIT>)+>
| <#FLOATEXP : ["E"](["+" , "-"])?(<DIGIT>)+>
| <#DIGIT  : ["0"-"9"]>
| <#INT_DECIMAL    : ["1"-"9"] (<DIGIT>)*>
| <#INT_OCTAL      : ["0"](["0"-"7"])*>
| <#INT_HEXADECIMAL    : ["0"]["x"](<DIGIT>|["a"-"f"]|["A"-"F"])*>
| <#LETTER : <UPPER_LETTER> | <LOWER_LETTER>>
| <#UPPER_LETTER : ["A"-"Z"]>
| <#LOWER_LETTER : ["a"-"z"]>
| <#SLASH  : ["/"]>

//begin special symbols
|<DOT : ".">
|<PLUS:"+">
|<MINUS:"-">
|<STAR:"*">
|<EQUAL:"=">
|<SEMICOLON:";">
|<COLON:":">
|<EQUALS:"==">
|<NOT_EQUALS:"!=">
|<LESS_THAN:"<">
|<LESS_EQUALS:"<=">
|<GREATER_EQUALS:">=">
|<GREATER_THAN:">">
|<BACKSLASH:"/">
|<LEFT_BRACE : "{">
|<RIGHT_BRACE : "}">

//error handling
|<ERROR : ~["\r", "\n"]> { debugStream.println("ERROR token: " + matchedToken.image); }
}

//error handling
JAVACODE
String handleError(Token token) {
	System.out.println("*** ERROR Line " + token.beginLine + " after \"" + token.image + "\"");

	Token t;

	do {
		t = getNextToken();
	}  while (t.kind != EOF);

	//  remove partially built AST node
	jjtree.popNode();
	return t.image;
}

## test.txt
<PROGRAM>

;statements
| = c 2

;function defs
[ func1 a b

 return + a b

]


;function calls
| print + c func1 2 3
| func1 b c

\fartknocker

;if statements
if  [< c 2
       | = c 3]


;cond statements (acting as a switch)
cond [ < c 2 ]
[ >= c 3
       | func1 b c]


;do statements
do d 10 (+ d 1)
[>= d 15
       | func1 b c]


</PROGRAM>

##Output
macbookpro13:HW7 kristen$ java HarveyParser test.txt
program
statement
arguments
IDENTIFIER token: c
arguments
NUMBER token: 2
function
functionname
IDENTIFIER token: func1
IDENTIFIER token: a
func_arguments
IDENTIFIER token: b
func_arguments
functionret
arguments
IDENTIFIER token: a
arguments
IDENTIFIER token: b
statement
arguments
IDENTIFIER token: c
arguments
IDENTIFIER token: func1
NUMBER token: 2
arguments
NUMBER token: 3
arguments
statement
IDENTIFIER token: func1
functionname
IDENTIFIER token: b
arguments
IDENTIFIER token: c
arguments
ERROR token: \
error
*** ERROR Line 18 after "\"
IDENTIFIER token: fartknocker
IDENTIFIER token: c
NUMBER token: 2
IDENTIFIER token: c
NUMBER token: 3
IDENTIFIER token: c
NUMBER token: 2
IDENTIFIER token: c
NUMBER token: 3
IDENTIFIER token: func1
IDENTIFIER token: b
IDENTIFIER token: c
IDENTIFIER token: d
NUMBER token: 10
IDENTIFIER token: d
NUMBER token: 1
IDENTIFIER token: d
NUMBER token: 15
IDENTIFIER token: func1
IDENTIFIER token: b
IDENTIFIER token: c