/* valagenieparser.vala
 *
 * Copyright (C) 2008-2012  Jamie McCracken, Jürg Billeter
 * Based on code by Jürg Billeter
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.

 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.

 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 *
 * Author:
 * 	Jamie McCracken jamiemcc gnome org
 */

using GLib;


/**
 * Code visitor parsing all Genie source files.
 */
public class Vala.Genie.Parser : CodeVisitor {
	Scanner scanner;

	CodeContext context;

	// token buffer
	TokenInfo[] tokens;
	// index of current token in buffer
	int index;
	// number of tokens in buffer
	int size;

	Comment comment;

	string class_name;

	/* hack needed to know if any part of an expression is a lambda one */
	bool current_expr_is_lambda;

	const int BUFFER_SIZE = 32;

	static List<TypeParameter> _empty_type_parameter_list;

	struct TokenInfo {
		public TokenType type;
		public SourceLocation begin;
		public SourceLocation end;
	}

	[Flags]
	enum ModifierFlags {
		NONE = 0,
		ABSTRACT,
		CLASS,
		EXTERN,
		INLINE,
		NEW,
		OVERRIDE,
		STATIC,
		VIRTUAL,
		PRIVATE,
		ASYNC,
		SEALED,
		PUBLIC,
		PROTECTED
	}

	public Parser () {
		tokens = new TokenInfo[BUFFER_SIZE];
		class_name = null;
		current_expr_is_lambda = false;
	}

	/**
	 * Parses all .gs source files in the specified code context and
	 * builds a code tree.
	 *
	 * @param context a code context
	 */
	public void parse (CodeContext context) {
		this.context = context;
		context.accept (this);
		this.context = null;
	}

	public override void visit_source_file (SourceFile source_file) {
		if (source_file.filename.has_suffix (".gs")) {
			parse_file (source_file);
		}
	}

	inline bool next () {
		index = (index + 1) % BUFFER_SIZE;
		size--;
		if (size <= 0) {
			SourceLocation begin, end;
			TokenType type = scanner.read_token (out begin, out end);
			tokens[index] = { type, begin, end };
			size = 1;
		}
		return (tokens[index].type != TokenType.EOF);
	}

	inline void prev () {
		index = (index - 1 + BUFFER_SIZE) % BUFFER_SIZE;
		size++;
		assert (size <= BUFFER_SIZE);
	}

	inline TokenType current () {
		return tokens[index].type;
	}

	inline bool accept (TokenType type) {
		if (current () == type) {
			next ();
			return true;
		}
		return false;
	}

	inline bool accept_separator () {
		if (current () == TokenType.COMMA || current () == TokenType.EOL) {
			next ();
			return true;
		}
		return false;
	}

	inline bool accept_terminator () {
		if (current () == TokenType.SEMICOLON || current () == TokenType.EOL) {
			next ();
			return true;
		}
		return false;
	}

	inline bool accept_block () {

		bool has_term = accept_terminator ();

		if (accept (TokenType.INDENT)) {
			prev();
			return true;
		}

		if (has_term) {
			prev ();
		}

		return false;
	}

	void report_parse_error (ParseError e) {
		var begin = get_location ();
		next ();
		Report.error (get_src (begin), "syntax error, %s", e.message);
	}

	inline bool expect (TokenType type) throws ParseError {
		if (accept (type)) {
			return true;
		}

		TokenType cur = current ();
		TokenType pre =  tokens[index - 1].type;

		throw new ParseError.SYNTAX ("expected %s but got %s with previous %s", type.to_string (), cur.to_string (), pre.to_string());
	}

	inline bool expect_separator () throws ParseError {
		if (accept_separator ()) {
			return true;
		}

		TokenType cur = current ();

		throw new ParseError.SYNTAX ("expected line end or comma but got %s", cur.to_string());
	}

	inline bool expect_terminator () throws ParseError {
		if (accept_terminator ()) {
			return true;
		}

		TokenType cur = current ();

		throw new ParseError.SYNTAX ("expected line end or semicolon but got %s", cur.to_string());
	}

	inline SourceLocation get_location () {
		return tokens[index].begin;
	}

	string get_current_string () {
		var token = tokens[index];
		return ((string) token.begin.pos).substring (0, (int) (token.end.pos - token.begin.pos));
	}

	string get_last_string () {
		int last_index = (index + BUFFER_SIZE - 1) % BUFFER_SIZE;
		var token = tokens[last_index];
		return ((string) token.begin.pos).substring (0, (int) (token.end.pos - token.begin.pos));
	}

	SourceReference get_src (SourceLocation begin) {
		int last_index = (index + BUFFER_SIZE - 1) % BUFFER_SIZE;

		return new SourceReference (scanner.source_file, begin, tokens[last_index].end);
	}

	SourceReference get_current_src () {
		var token = tokens[index];
		return new SourceReference (scanner.source_file, token.begin, token.end);
	}

	void rollback (SourceLocation location) {
		while (tokens[index].begin.pos != location.pos) {
			index = (index - 1 + BUFFER_SIZE) % BUFFER_SIZE;
			size++;
			if (size > BUFFER_SIZE) {
				scanner.seek (location);
				size = 0;
				index = 0;

				next ();
			}
		}
	}

	inline  SymbolAccessibility get_default_accessibility (string s) {
		if (s.has_prefix("_")) {
			return SymbolAccessibility.PRIVATE;
		}

		return SymbolAccessibility.PUBLIC;
	}

	void skip_identifier () throws ParseError {
		// also accept keywords as identifiers where there is no conflict
		switch (current ()) {
		case TokenType.ABSTRACT:
		case TokenType.AS:
		case TokenType.ASSERT:
		case TokenType.ASYNC:
		case TokenType.BREAK:
		case TokenType.CLASS:
		case TokenType.CONST:
		case TokenType.CONTINUE:
		case TokenType.DEDENT:
		case TokenType.DEF:
		case TokenType.DEFAULT:
		case TokenType.DELEGATE:
		case TokenType.DELETE:
		case TokenType.DO:
		case TokenType.DOWNTO:
		case TokenType.DYNAMIC:
		case TokenType.ELSE:
		case TokenType.EOL:
		case TokenType.ENUM:
		case TokenType.ENSURES:
		case TokenType.EVENT:
		case TokenType.EXCEPT:
		case TokenType.EXCEPTION:
		case TokenType.EXTERN:
		case TokenType.FALSE:
		case TokenType.FINAL:
		case TokenType.FINALLY:
		case TokenType.FOR:
		case TokenType.GET:
		case TokenType.IDENTIFIER:
		case TokenType.IF:
		case TokenType.IN:
		case TokenType.INDENT:
		case TokenType.INIT:
		case TokenType.INLINE:
		case TokenType.INTERFACE:
		case TokenType.INTERNAL:
		case TokenType.IS:
		case TokenType.ISA:
		case TokenType.LOCK:
		case TokenType.NAMESPACE:
		case TokenType.NEW:
		case TokenType.NULL:
		case TokenType.OF:
		case TokenType.OUT:
		case TokenType.OVERRIDE:
		case TokenType.OWNED:
		case TokenType.PASS:
		case TokenType.PRINT:
		case TokenType.PRIVATE:
		case TokenType.PROTECTED:
		case TokenType.PROP:
		case TokenType.RAISE:
		case TokenType.RAISES:
		case TokenType.REF:
		case TokenType.REQUIRES:
		case TokenType.RETURN:
		case TokenType.SEALED:
		case TokenType.SELF:
		case TokenType.SET:
		case TokenType.SIZEOF:
		case TokenType.STATIC:
		case TokenType.STRUCT:
		case TokenType.SUPER:
		case TokenType.TO:
		case TokenType.TRUE:
		case TokenType.TRY:
		case TokenType.TYPEOF:
		case TokenType.UNOWNED:
		case TokenType.USES:
		case TokenType.VAR:
		case TokenType.VIRTUAL:
		case TokenType.VOID:
		case TokenType.VOLATILE:
		case TokenType.WEAK:
		case TokenType.WHEN:
		case TokenType.WHILE:
		case TokenType.YIELD:
			next ();
			return;
		case TokenType.INTEGER_LITERAL:
		case TokenType.REAL_LITERAL:
			// also accept integer and real literals
			// as long as they contain at least one character
			// and no decimal point
			// for example, 2D and 3D
			string id = get_current_string ();
			if (id[id.length - 1].isalpha () && !("." in id)) {
				next ();
				return;
			}
			break;
		default:
			break;
		}

		throw new ParseError.SYNTAX ("expected identifier");
	}

	string parse_identifier () throws ParseError {
		skip_identifier ();
		return get_last_string ();
	}

	Expression parse_literal () throws ParseError {
		var begin = get_location ();

		switch (current ()) {
		case TokenType.TRUE:
			next ();
			return new BooleanLiteral (true, get_src (begin));
		case TokenType.FALSE:
			next ();
			return new BooleanLiteral (false, get_src (begin));
		case TokenType.INTEGER_LITERAL:
			next ();
			return new IntegerLiteral (get_last_string (), get_src (begin));
		case TokenType.REAL_LITERAL:
			next ();
			return new RealLiteral (get_last_string (), get_src (begin));
		case TokenType.CHARACTER_LITERAL:
			next ();
			// FIXME validate and unescape here and just pass unichar to CharacterLiteral
			var lit = new CharacterLiteral (get_last_string (), get_src (begin));
			if (lit.error) {
				Report.error (lit.source_reference, "invalid character literal");
			}
			return lit;
		case TokenType.REGEX_LITERAL:
			next ();
			string match_part = get_last_string ();
			SourceReference src_begin = get_src (begin);
			expect (TokenType.CLOSE_REGEX_LITERAL);
			string close_token = get_last_string ();
			return new RegexLiteral ("%s/%s".printf (close_token, match_part), src_begin);
		case TokenType.STRING_LITERAL:
			next ();
			return new StringLiteral (get_last_string (), get_src (begin));
		case TokenType.TEMPLATE_STRING_LITERAL:
			next ();
			return new StringLiteral ("\"%s\"".printf (get_last_string ()), get_src (begin));
		case TokenType.VERBATIM_STRING_LITERAL:
			next ();
			string raw_string = get_last_string ();
			string escaped_string = raw_string.substring (3, raw_string.length - 6).escape ("");
			return new StringLiteral ("\"%s\"".printf (escaped_string), get_src (begin));
		case TokenType.VERBATIM_TEMPLATE_STRING_LITERAL:
			next ();
			string raw_string = get_last_string ();
			string escaped_string = raw_string.escape ("");
			return new StringLiteral ("\"%s\"".printf (escaped_string), get_src (begin));
		case TokenType.NULL:
			next ();
			return new NullLiteral (get_src (begin));
		default:
			throw new ParseError.SYNTAX ("expected literal");
		}
	}

	public void parse_file (SourceFile source_file) {
		var has_global_context = (context != null);
		if (!has_global_context) {
			context = source_file.context;
		}

		scanner = new Scanner (source_file);
		scanner.parse_file_comments ();
		scanner.indent_spaces = 0;
		index = -1;
		size = 0;

		next ();

		try {
			var begin = get_location ();
			/* see if there is an indent attribute */
			if (accept (TokenType.OPEN_BRACKET)) {
				var id = parse_identifier ();
				if (id == "indent") {
					expect (TokenType.ASSIGN);
					expect (TokenType.INTEGER_LITERAL);
					scanner.indent_spaces = int.parse (get_last_string());
					expect (TokenType.CLOSE_BRACKET);
					expect (TokenType.EOL);
				} else {
					rollback (begin);
				}
			}

			parse_using_directives (context.root);
			parse_declarations (context.root, true);
		} catch (ParseError e) {
			report_parse_error (e);
		}

		scanner = null;
		if (!has_global_context) {
			context = null;
		}
	}

	void skip_symbol_name () throws ParseError {
		do {
			skip_identifier ();
		} while (accept (TokenType.DOT));
	}

	UnresolvedSymbol parse_symbol_name () throws ParseError {
		var begin = get_location ();
		UnresolvedSymbol sym = null;
		do {
			string name = parse_identifier ();
			sym = new UnresolvedSymbol (sym, name, get_src (begin));
		} while (accept (TokenType.DOT));
		return sym;
	}

	void skip_type () throws ParseError {

		accept (TokenType.DYNAMIC);
		accept (TokenType.OWNED);
		accept (TokenType.UNOWNED);
		accept (TokenType.WEAK);


		if (accept (TokenType.ARRAY) || accept (TokenType.LIST) || accept (TokenType.DICT)) {
			accept (TokenType.OF);
		}

		if (accept (TokenType.VOID)) {
		} else {
			skip_symbol_name ();
			skip_type_argument_list ();
		}

		while (accept (TokenType.OPEN_BRACKET)) {
			do {
				if (current () != TokenType.COMMA && current () != TokenType.CLOSE_BRACKET) {
					parse_expression ();
				}
			} while (accept (TokenType.COMMA));
			expect (TokenType.CLOSE_BRACKET);
		}
		accept (TokenType.OP_NEG);
		accept (TokenType.INTERR);
	}


	Expression parse_regex_literal () throws ParseError {
		expect (TokenType.OPEN_REGEX_LITERAL);

		var expr = parse_literal ();

		return expr;
	}

	DataType parse_type (bool owned_by_default, bool can_weak_ref) throws ParseError {
		var begin = get_location ();

		List<DataType> type_arg_list = null;
		UnresolvedSymbol sym = null;

		bool is_dynamic = accept (TokenType.DYNAMIC);
		bool value_owned = owned_by_default;
		bool is_nullable = false;

		if (owned_by_default) {
			if (accept (TokenType.UNOWNED)) {
				value_owned = false;
			} else if (accept (TokenType.WEAK)) {
				if (!can_weak_ref && !context.deprecated) {
					Report.warning (get_src (begin), "deprecated syntax, use `unowned` modifier");
				}
				value_owned = false;
			}
		} else {
			value_owned = accept (TokenType.OWNED);
		}

		/* handle arrays */
		bool is_array = false;

		if (accept (TokenType.ARRAY)) {
			expect (TokenType.OF);
			is_array = true;
		}

		/* handle lists */
		bool is_list = false;

		if (accept (TokenType.LIST)) {
			expect (TokenType.OF);
			prev ();
			is_list = true;
		}

		/* handle dicts */
		bool is_dict = false;

		if (accept (TokenType.DICT)) {
			expect (TokenType.OF);
			prev ();
			is_dict = true;
		}

		DataType type;

		if (!is_dynamic && value_owned == owned_by_default && accept (TokenType.VOID)) {
			type = new VoidType (get_src (begin));
		} else {

			if (is_list) {
				var sym_parent = new UnresolvedSymbol (null, "Gee", get_src (begin));
				sym = new UnresolvedSymbol (sym_parent, "ArrayList", get_src (begin));
			} else if (is_dict) {
				var sym_parent = new UnresolvedSymbol (null, "Gee", get_src (begin));
				sym = new UnresolvedSymbol (sym_parent, "HashMap", get_src (begin));
			} else {
				sym = parse_symbol_name ();
			}

			is_nullable = accept (TokenType.INTERR);

			type_arg_list = parse_type_argument_list (false);

			type = new UnresolvedType.from_symbol (sym, get_src (begin));
			if (type_arg_list != null) {
				foreach (DataType type_arg in type_arg_list) {
					type.add_type_argument (type_arg);
				}
			}
		}

		while (accept (TokenType.STAR)) {
			 type = new PointerType (type, get_src (begin));
		}

		if (!(type is PointerType)) {
			type.nullable = is_nullable;
		}

		if (is_array) {

			if (!accept (TokenType.OPEN_BRACKET)) {
				type.value_owned = true;
				type = new ArrayType (type, 1, get_src (begin));
				type.nullable = accept (TokenType.INTERR);

			} else {
				prev ();

				while (accept (TokenType.OPEN_BRACKET))	{
					bool invalid_array = false;
					int array_rank = 0;
					do {
						array_rank++;
						// required for decision between expression and declaration statement
						if (current () != TokenType.COMMA && current () != TokenType.CLOSE_BRACKET) {
							parse_expression ();
							// only used for parsing, reject use as real type
							invalid_array = true;
						}
					} while (accept (TokenType.COMMA));
					expect (TokenType.CLOSE_BRACKET);

					type.value_owned = true;
					var array_type = new ArrayType (type, array_rank, get_src (begin));
					array_type.nullable = accept (TokenType.INTERR);

					array_type.invalid_syntax = invalid_array;

					type = array_type;
				}
			}
		}

		if (type is PointerType) {
			value_owned = false;
		}

		type.is_dynamic = is_dynamic;
		type.value_owned = value_owned;
		return type;
	}

	DataType? parse_inline_array_type (DataType? type) throws ParseError {
		var begin = get_location ();

		// inline-allocated array
		if (type != null && accept (TokenType.OPEN_BRACKET)) {
			Expression array_length = null;

			if (current () != TokenType.CLOSE_BRACKET) {
				array_length = parse_expression ();
 			}
			expect (TokenType.CLOSE_BRACKET);

			var array_type = new ArrayType (type, 1, get_src (begin));
			array_type.inline_allocated = true;
			if (array_length != null) {
				array_type.fixed_length = true;
				array_type.length = array_length;
			}
			array_type.value_owned = type.value_owned;
			return array_type;
		}
		return type;
	}


	List<Expression> parse_argument_list () throws ParseError {
		var list = new ArrayList<Expression> ();
		if (current () != TokenType.CLOSE_PARENS) {
			do {
				list.add (parse_argument ());
			} while (accept (TokenType.COMMA));
		}
		return list;
	}

	Expression parse_argument () throws ParseError {
		var begin = get_location ();

		if (accept (TokenType.REF)) {
			var inner = parse_expression ();
			return new UnaryExpression (UnaryOperator.REF, inner, get_src (begin));
		} else if (accept (TokenType.OUT)) {
			var inner = parse_expression ();
			return new UnaryExpression (UnaryOperator.OUT, inner, get_src (begin));
		} else {
			var expr = parse_expression ();
			var ma = expr as MemberAccess;
			if (ma != null && ma.inner == null && accept (TokenType.COLON)) {
				// named argument
				expr = parse_expression ();
				return new NamedArgument (ma.member_name, expr, get_src (begin));
			} else {
				return expr;
			}

		}
	}

	Expression parse_primary_expression () throws ParseError {
		var begin = get_location ();

		Expression expr;

		switch (current ()) {
		case TokenType.TRUE:
		case TokenType.FALSE:
		case TokenType.INTEGER_LITERAL:
		case TokenType.REAL_LITERAL:
		case TokenType.CHARACTER_LITERAL:
		case TokenType.REGEX_LITERAL:
		case TokenType.STRING_LITERAL:
		case TokenType.TEMPLATE_STRING_LITERAL:
		case TokenType.VERBATIM_STRING_LITERAL:
		case TokenType.VERBATIM_TEMPLATE_STRING_LITERAL:
		case TokenType.NULL:
			expr = parse_literal ();
			break;
		case TokenType.ASSERT:
			return parse_assert_expression ();
		case TokenType.OPEN_BRACE:
			expr = parse_initializer ();
			break;
		case TokenType.OPEN_PARENS:
			expr = parse_tuple ();
			break;
		case TokenType.OPEN_REGEX_LITERAL:
			expr = parse_regex_literal ();
			break;
		case TokenType.OPEN_TEMPLATE:
			expr = parse_template ();
			break;
		case TokenType.SELF:
			expr = parse_this_access ();
			break;
		case TokenType.SUPER:
			expr = parse_base_access ();
			break;
		case TokenType.NEW:
			expr = parse_object_or_array_creation_expression ();
			break;
		case TokenType.PRINT:
			return parse_print_expression ();
		case TokenType.SIZEOF:
			expr = parse_sizeof_expression ();
			break;
		case TokenType.TYPEOF:
			expr = parse_typeof_expression ();
			break;
		case TokenType.YIELD:
			expr = parse_yield_expression ();
			break;
		default:
			expr = parse_simple_name ();
			break;
		}

		// process primary expressions that start with an inner primary expression
		bool found = true;
		while (found) {
			switch (current ()) {
			case TokenType.DOT:
				expr = parse_member_access (begin, expr);
				break;
			case TokenType.OP_PTR:
				expr = parse_pointer_member_access (begin, expr);
				break;
			case TokenType.OPEN_PARENS:
				expr = parse_method_call (begin, expr);
				break;
			case TokenType.OPEN_BRACKET:
				expr = parse_element_access (begin, expr);
				break;
			case TokenType.OP_INC:
				expr = parse_post_increment_expression (begin, expr);
				break;
			case TokenType.OP_DEC:
				expr = parse_post_decrement_expression (begin, expr);
				break;

			default:
				found = false;
				break;
			}
		}

		return expr;
	}

	Expression parse_simple_name () throws ParseError {
		var begin = get_location ();
		string id = parse_identifier ();
		List<DataType> type_arg_list = parse_type_argument_list (true);
		var expr = new MemberAccess (null, id, get_src (begin));
		if (type_arg_list != null) {
			foreach (DataType type_arg in type_arg_list) {
				expr.add_type_argument (type_arg);
			}
		}
		return expr;
	}

	Expression parse_template () throws ParseError {
		var begin = get_location ();
		var template = new Template ();

		expect (TokenType.OPEN_TEMPLATE);
		while (current () != TokenType.CLOSE_TEMPLATE) {
			template.add_expression (parse_expression ());
			expect (TokenType.COMMA);
		}
		expect (TokenType.CLOSE_TEMPLATE);

		template.source_reference = get_src (begin);
		return template;
	}

	Expression parse_tuple () throws ParseError {
		expect (TokenType.OPEN_PARENS);
		var expr_list = new ArrayList<Expression> ();
		if (current () != TokenType.CLOSE_PARENS) {
			do {
				expr_list.add (parse_expression ());
			} while (accept (TokenType.COMMA));
		}
		expect (TokenType.CLOSE_PARENS);
		if (expr_list.size != 1) {
			var tuple = new Tuple ();
			foreach (Expression expr in expr_list) {
				tuple.add_expression (expr);
			}
			return tuple;
		}
		return expr_list.get (0);
	}

	Expression parse_member_access (SourceLocation begin, Expression inner) throws ParseError {
		expect (TokenType.DOT);
		string id = parse_identifier ();
		List<DataType> type_arg_list = parse_type_argument_list (true);
		var expr = new MemberAccess (inner, id, get_src (begin));
		if (type_arg_list != null) {
			foreach (DataType type_arg in type_arg_list) {
				expr.add_type_argument (type_arg);
			}
		}
		return expr;
	}

	Expression parse_pointer_member_access (SourceLocation begin, Expression inner) throws ParseError {
		expect (TokenType.OP_PTR);
		string id = parse_identifier ();
		List<DataType> type_arg_list = parse_type_argument_list (true);
		var expr = new MemberAccess.pointer (inner, id, get_src (begin));
		if (type_arg_list != null) {
			foreach (DataType type_arg in type_arg_list) {
				expr.add_type_argument (type_arg);
			}
		}
		return expr;
	}


	List<Expression> parse_print_argument_list () throws ParseError {
		var list = new ArrayList<Expression> ();
		var i = 0;
		var begin = get_location ();

		if (current () != TokenType.CLOSE_PARENS) {
			do {
				var p_expr = parse_expression ();
				if (i == 0) {
					i++;

					if (p_expr != null) {
						if (p_expr is StringLiteral) {
							var s_exp = (StringLiteral) p_expr;
							var len = s_exp.value.length;

							if (len > 2) {
								string s = "\\n\"";
								var st =  s_exp.value.substring (0, len-1);
								st += s;
								s_exp.value = st;
							} else {
								string s = "\"\\n\"";
								p_expr = new StringLiteral (s, get_src (begin));
							}
						} else {
							string s = "\"%s\\n\"";
							var s_exp = new StringLiteral (s, get_src (begin));
							list.add (s_exp);
						}
					}
				}
				list.add (p_expr);

			} while (accept (TokenType.COMMA));
		}
		return list;
	}

	Expression parse_print_expression () throws ParseError {
		var begin = get_location ();

		expect (TokenType.PRINT);
		bool parens = accept (TokenType.OPEN_PARENS);

		var expr = new MemberAccess (null, "print", get_src (begin));

		var arg_list = parse_print_argument_list ();

		if (parens) {
			expect (TokenType.CLOSE_PARENS);
		}

		var print_expr = new MethodCall (expr, get_src (begin));

		foreach (Expression arg in arg_list) {
			print_expr.add_argument (arg);
		}

		return print_expr;

	}

	Expression parse_assert_expression () throws ParseError {
		var begin = get_location ();

		expect (TokenType.ASSERT);
		bool parens = accept (TokenType.OPEN_PARENS);

		var expr = new MemberAccess (null, "assert", get_src (begin));

		var arg_list = parse_argument_list ();

		if (parens) {
			expect (TokenType.CLOSE_PARENS);
		}

		var assert_expr = new MethodCall (expr, get_src (begin));

		foreach (Expression arg in arg_list) {
			assert_expr.add_argument (arg);
		}

		return assert_expr;

	}

	Expression parse_method_call (SourceLocation begin, Expression inner) throws ParseError {
		expect (TokenType.OPEN_PARENS);
		var arg_list = parse_argument_list ();
		expect (TokenType.CLOSE_PARENS);

		var init_list = parse_object_initializer ();

		if (init_list.size > 0 && inner is MemberAccess) {
			// struct creation expression
			var member = (MemberAccess) inner;

			var expr = new ObjectCreationExpression (member, get_src (begin));
			expr.struct_creation = true;
			foreach (Expression arg in arg_list) {
				expr.add_argument (arg);
			}
			foreach (MemberInitializer initializer in init_list) {
				expr.add_member_initializer (initializer);
			}
			return expr;
		} else {
			var expr = new MethodCall (inner, get_src (begin));
			foreach (Expression arg in arg_list) {
				expr.add_argument (arg);
			}
			return expr;
		}
	}

	Expression parse_element_access (SourceLocation begin, Expression inner) throws ParseError {
		Expression? stop = null;
		List<Expression> index_list;

		expect (TokenType.OPEN_BRACKET);
		if (current () == TokenType.COLON) {
			// slice expression
			index_list = new ArrayList<Expression> ();
			index_list.add (new IntegerLiteral ("0", get_src (begin)));
		} else {
			index_list = parse_expression_list ();
		}

		if (index_list.size == 1 && accept (TokenType.COLON)) {
			// slice expression
			if (current () == TokenType.CLOSE_BRACKET) {
				stop = new MemberAccess (inner, "length", get_src (begin));
			} else {
				stop = parse_expression ();
			}
		}
		expect (TokenType.CLOSE_BRACKET);

		if (stop == null) {
			var expr = new ElementAccess (inner, get_src (begin));
			foreach (Expression index in index_list) {
				expr.append_index (index);
			}
			return expr;
		} else {
			return new SliceExpression (inner, index_list[0], stop, get_src (begin));
		}
	}

	List<Expression> parse_expression_list () throws ParseError {
		var list = new ArrayList<Expression> ();
		do {
			list.add (parse_expression ());
		} while (accept (TokenType.COMMA));
		return list;
	}

	Expression parse_this_access () throws ParseError {
		var begin = get_location ();
		expect (TokenType.SELF);
		return new MemberAccess (null, "this", get_src (begin));
	}

	Expression parse_base_access () throws ParseError {
		var begin = get_location ();
		expect (TokenType.SUPER);
		return new BaseAccess (get_src (begin));
	}

	Expression parse_post_increment_expression (SourceLocation begin, Expression inner) throws ParseError {
		expect (TokenType.OP_INC);
		return new PostfixExpression (inner, true, get_src (begin));
	}

	Expression parse_post_decrement_expression (SourceLocation begin, Expression inner) throws ParseError {
		expect (TokenType.OP_DEC);
		return new PostfixExpression (inner, false, get_src (begin));
	}

	Expression parse_object_or_array_creation_expression () throws ParseError {
		var begin = get_location ();
		expect (TokenType.NEW);

		if (accept (TokenType.ARRAY)) {
			expect (TokenType.OF);
			var mtype = parse_type (true, false);
			var expr = parse_array_creation_expression (begin, mtype);
			return expr;
		}

		if (accept (TokenType.LIST)) {
			expect (TokenType.OF);
			var mtype = parse_type (true, false);
			var expr = parse_list_creation_expression (begin, mtype);
			return expr;
		}

		if (accept (TokenType.DICT)) {
			expect (TokenType.OF);
			var mtype1 = parse_type (true, false);
			expect (TokenType.COMMA);
			var mtype2 = parse_type (true, false);
			var expr = parse_dict_creation_expression (begin, mtype1, mtype2);
			return expr;
		}


		var member = parse_member_name ();
		var expr = parse_object_creation_expression (begin, member);
		return expr;

	}

	Expression parse_object_creation_expression (SourceLocation begin, MemberAccess member) throws ParseError {
		List<Expression> arg_list;
		if (accept (TokenType.OPEN_PARENS)) {
			arg_list = parse_argument_list ();
			expect (TokenType.CLOSE_PARENS);
		} else {
			arg_list = new ArrayList<Expression> ();
		}

		var init_list = parse_object_initializer ();

		var expr = new ObjectCreationExpression (member, get_src (begin));
		foreach (Expression arg in arg_list) {
			expr.add_argument (arg);
		}
		foreach (MemberInitializer initializer in init_list) {
			expr.add_member_initializer (initializer);
		}
		return expr;
	}

	Expression parse_array_creation_expression (SourceLocation begin, DataType element_type) throws ParseError {
		bool size_specified = false;
		List<Expression> size_specifier_list = null;
		bool first = true;
		DataType etype = element_type.copy ();

		var has_bracket = accept (TokenType.OPEN_BRACKET);

		do {
			if (!first) {
 				// array of arrays: new T[][42]

 				if (size_specified) {
					throw new ParseError.SYNTAX ("size of inner arrays must not be specified in array creation expression");
				}

				etype = new ArrayType (etype, size_specifier_list.size, etype.source_reference);
			} else {
				first = false;
			}

			size_specifier_list = new ArrayList<Expression> ();
			do {
				Expression size = null;
				if (has_bracket && current () != TokenType.CLOSE_BRACKET && current () != TokenType.COMMA) {
					size = parse_expression ();
					size_specified = true;
				}
				size_specifier_list.add (size);
			} while (accept (TokenType.COMMA));

			if (has_bracket) {
				expect (TokenType.CLOSE_BRACKET);
			}
		} while (accept (TokenType.OPEN_BRACKET));

		InitializerList initializer = null;
		if (accept (TokenType.ASSIGN)) {
			initializer = parse_initializer ();
		}

		var expr = new ArrayCreationExpression (etype, size_specifier_list.size, initializer, get_src (begin));
		if (size_specified) {
			foreach (Expression size in size_specifier_list) {
				expr.append_size (size);
			}
		}
		return expr;
	}


	Expression parse_list_creation_expression (SourceLocation begin, DataType element_type) throws ParseError {

		MemberAccess list_member = null, parent_member = null;

		parent_member = new MemberAccess (null, "Gee", get_src (begin));
		list_member = new MemberAccess (parent_member, "ArrayList", get_src (begin));
		list_member.add_type_argument (element_type);

		var expr = new ObjectCreationExpression (list_member, get_src (begin));
		return expr;
	}

	Expression parse_dict_creation_expression (SourceLocation begin, DataType key_type, DataType value_type) throws ParseError {

		MemberAccess dict_member = null, parent_member = null;

		parent_member = new MemberAccess (null, "Gee", get_src (begin));
		dict_member = new MemberAccess (parent_member, "HashMap", get_src (begin));
		dict_member.add_type_argument (key_type);
		dict_member.add_type_argument (value_type);

		var expr = new ObjectCreationExpression (dict_member, get_src (begin));

		return expr;
	}


	List<MemberInitializer> parse_object_initializer () throws ParseError {
		var list = new ArrayList<MemberInitializer> ();
		if (accept (TokenType.OPEN_BRACE)) {
			do {
				list.add (parse_member_initializer ());
			} while (accept (TokenType.COMMA));
			expect (TokenType.CLOSE_BRACE);
		}
		return list;
	}

	MemberInitializer parse_member_initializer () throws ParseError {
		var begin = get_location ();
		string id = parse_identifier ();
		expect (TokenType.ASSIGN);

		var inner = get_location ();
		Expression expr;
		try {
			// chained member initializer
			expr = parse_member_initializer ();
		} catch {
			rollback (inner);
			expr = parse_expression ();
		}
		return new MemberInitializer (id, expr, get_src (begin));
	}

	Expression parse_yield_expression () throws ParseError {
		expect (TokenType.YIELD);

		var expr = parse_expression ();

		unowned MethodCall? call = expr as MethodCall;
		unowned ObjectCreationExpression? object_creation = expr as ObjectCreationExpression;
		if (call == null && object_creation == null) {
			Report.error (expr.source_reference, "syntax error, expected method call");
			throw new ParseError.SYNTAX ("expected method call");
		}

		if (call != null) {
			call.is_yield_expression = true;
		} else if (object_creation != null) {
			object_creation.is_yield_expression = true;
		}

		return expr;
	}

	Expression parse_sizeof_expression () throws ParseError {
		var begin = get_location ();
		expect (TokenType.SIZEOF);
		expect (TokenType.OPEN_PARENS);
		var type = parse_type (true, false);
		expect (TokenType.CLOSE_PARENS);

		return new SizeofExpression (type, get_src (begin));
	}

	Expression parse_typeof_expression () throws ParseError {
		var begin = get_location ();
		expect (TokenType.TYPEOF);
		expect (TokenType.OPEN_PARENS);
		var type = parse_type (true, false);
		expect (TokenType.CLOSE_PARENS);

		return new TypeofExpression (type, get_src (begin));
	}

	UnaryOperator get_unary_operator (TokenType token_type) {
		switch (token_type) {
		case TokenType.PLUS:   return UnaryOperator.PLUS;
		case TokenType.MINUS:  return UnaryOperator.MINUS;
		case TokenType.OP_NEG: return UnaryOperator.LOGICAL_NEGATION;
		case TokenType.TILDE:  return UnaryOperator.BITWISE_COMPLEMENT;
		case TokenType.OP_INC: return UnaryOperator.INCREMENT;
		case TokenType.OP_DEC: return UnaryOperator.DECREMENT;
		default:			   return UnaryOperator.NONE;
		}
	}

	Expression parse_unary_expression () throws ParseError {
		var begin = get_location ();
		var operator = get_unary_operator (current ());
		if (operator != UnaryOperator.NONE) {
			next ();
			var op = parse_unary_expression ();
			return new UnaryExpression (operator, op, get_src (begin));
		}
		switch (current ()) {
		case TokenType.OPEN_PARENS:
			next ();
			switch (current ()) {
			case TokenType.OWNED:
				// (owned) foo
				next ();
				if (accept (TokenType.CLOSE_PARENS)) {
					var op = parse_unary_expression ();
					return new ReferenceTransferExpression (op, get_src (begin));
				}
				break;
			case TokenType.VOID:
			case TokenType.DYNAMIC:
			case TokenType.IDENTIFIER:
			case TokenType.ARRAY:
			case TokenType.LIST:
			case TokenType.DICT:
				var type = parse_type (true, false);
				if (accept (TokenType.CLOSE_PARENS)) {
					// check follower to decide whether to create cast expression
					switch (current ()) {
					case TokenType.OP_NEG:
					case TokenType.TILDE:
					case TokenType.OPEN_PARENS:
					case TokenType.TRUE:
					case TokenType.FALSE:
					case TokenType.INTEGER_LITERAL:
					case TokenType.REAL_LITERAL:
					case TokenType.CHARACTER_LITERAL:
					case TokenType.REGEX_LITERAL:
					case TokenType.STRING_LITERAL:
					case TokenType.TEMPLATE_STRING_LITERAL:
					case TokenType.VERBATIM_STRING_LITERAL:
					case TokenType.VERBATIM_TEMPLATE_STRING_LITERAL:
					case TokenType.NULL:
					case TokenType.SELF:
					case TokenType.SUPER:
					case TokenType.NEW:
					case TokenType.SIZEOF:
					case TokenType.TYPEOF:
					case TokenType.IDENTIFIER:
					case TokenType.PARAMS:
					case TokenType.YIELD:
						var inner = parse_unary_expression ();
						return new CastExpression (inner, type, get_src (begin));
					default:
						break;
					}
				}
				break;
			case TokenType.OP_NEG:
				next ();
				if (accept (TokenType.CLOSE_PARENS)) {
					// (!) non-null cast
					var inner = parse_unary_expression ();
					return new CastExpression.non_null (inner, get_src (begin));
				}
				break;

			default:
				break;
			}
			// no cast expression
			rollback (begin);
			break;
		case TokenType.STAR:
			next ();
			var op = parse_unary_expression ();
			return new PointerIndirection (op, get_src (begin));
		case TokenType.BITWISE_AND:
			next ();
			var op = parse_unary_expression ();
			return new AddressofExpression (op, get_src (begin));
		default:
			break;
		}

		var expr = parse_primary_expression ();
		return expr;
	}

	BinaryOperator get_binary_operator (TokenType token_type) {
		switch (token_type) {
		case TokenType.STAR:	return BinaryOperator.MUL;
		case TokenType.DIV:	 return BinaryOperator.DIV;
		case TokenType.PERCENT: return BinaryOperator.MOD;
		case TokenType.PLUS:	return BinaryOperator.PLUS;
		case TokenType.MINUS:   return BinaryOperator.MINUS;
		case TokenType.OP_LT:   return BinaryOperator.LESS_THAN;
		case TokenType.OP_GT:   return BinaryOperator.GREATER_THAN;
		case TokenType.OP_LE:   return BinaryOperator.LESS_THAN_OR_EQUAL;
		case TokenType.OP_GE:   return BinaryOperator.GREATER_THAN_OR_EQUAL;
		case TokenType.OP_EQ:   return BinaryOperator.EQUALITY;
		case TokenType.IS:
			next();
			if (current () == TokenType.OP_NEG) {
				prev ();
				return BinaryOperator.INEQUALITY;
			}
			prev ();
			return BinaryOperator.EQUALITY;
		case TokenType.OP_NE:   return BinaryOperator.INEQUALITY;
		default:				return BinaryOperator.NONE;
		}
	}

	Expression parse_multiplicative_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_unary_expression ();
		bool found = true;
		while (found) {
			var operator = get_binary_operator (current ());
			switch (operator) {
			case BinaryOperator.MUL:
			case BinaryOperator.DIV:
			case BinaryOperator.MOD:
				next ();
				var right = parse_unary_expression ();
				left = new BinaryExpression (operator, left, right, get_src (begin));
				break;
			default:
				found = false;
				break;
			}
		}
		return left;
	}

	Expression parse_additive_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_multiplicative_expression ();
		bool found = true;
		while (found) {
			var operator = get_binary_operator (current ());
			switch (operator) {
			case BinaryOperator.PLUS:
			case BinaryOperator.MINUS:
				next ();
				var right = parse_multiplicative_expression ();
				left = new BinaryExpression (operator, left, right, get_src (begin));
				break;
			default:
				found = false;
				break;
			}
		}
		return left;
	}

	Expression parse_shift_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_additive_expression ();
		bool found = true;
		while (found) {
			switch (current ()) {
			case TokenType.OP_SHIFT_LEFT:
				next ();
				var right = parse_additive_expression ();
				left = new BinaryExpression (BinaryOperator.SHIFT_LEFT, left, right, get_src (begin));
				break;
			// don't use OP_SHIFT_RIGHT to support >> for nested generics
			case TokenType.OP_GT:
				char* first_gt_pos = tokens[index].begin.pos;
				next ();
				// only accept >> when there is no space between the two > signs
				if (current () == TokenType.OP_GT && tokens[index].begin.pos == first_gt_pos + 1) {
					next ();
					var right = parse_additive_expression ();
					left = new BinaryExpression (BinaryOperator.SHIFT_RIGHT, left, right, get_src (begin));
				} else {
					prev ();
					found = false;
				}
				break;
			default:
				found = false;
				break;
			}
		}
		return left;
	}

	Expression parse_type_check_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_shift_expression ();
		if (accept (TokenType.ISA)) {
			var type = parse_type (true, false);
			left = new TypeCheck (left, type, get_src (begin));
		} else if (accept (TokenType.AS)) {
			var type = parse_type (true, false);
			left = new CastExpression.silent (left, type, get_src (begin));
		}
		return left;
	}

	Expression parse_relational_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_type_check_expression ();
		bool found = true;
		while (found) {
			var operator = get_binary_operator (current ());
			switch (operator) {
			case BinaryOperator.LESS_THAN:
			case BinaryOperator.LESS_THAN_OR_EQUAL:
			case BinaryOperator.GREATER_THAN_OR_EQUAL:
				next ();
				var right = parse_type_check_expression ();
				left = new BinaryExpression (operator, left, right, get_src (begin));
				break;
			case BinaryOperator.GREATER_THAN:
				next ();
				// ignore >> and >>= (two tokens due to generics)
				if (current () != TokenType.OP_GT && current () != TokenType.OP_GE) {
					var right = parse_type_check_expression ();
					left = new BinaryExpression (operator, left, right, get_src (begin));
				} else {
					prev ();
					found = false;
				}
				break;
			default:
				found = false;
				break;
			}
		}
		return left;
	}

	Expression parse_equality_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_relational_expression ();
		bool found = true;
		while (found) {
			var operator = get_binary_operator (current ());
			switch (operator) {
			case BinaryOperator.INEQUALITY:
			case BinaryOperator.EQUALITY:
				if ((operator == BinaryOperator.INEQUALITY) && (current () == TokenType.IS)) {
					next ();
				}
				next ();
				var right = parse_relational_expression ();
				left = new BinaryExpression (operator, left, right, get_src (begin));
				break;
			default:
				found = false;
				break;
			}
		}
		return left;
	}

	Expression parse_and_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_equality_expression ();
		while (accept (TokenType.BITWISE_AND)) {
			var right = parse_equality_expression ();
			left = new BinaryExpression (BinaryOperator.BITWISE_AND, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_exclusive_or_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_and_expression ();
		while (accept (TokenType.CARRET)) {
			var right = parse_and_expression ();
			left = new BinaryExpression (BinaryOperator.BITWISE_XOR, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_inclusive_or_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_exclusive_or_expression ();
		while (accept (TokenType.BITWISE_OR)) {
			var right = parse_exclusive_or_expression ();
			left = new BinaryExpression (BinaryOperator.BITWISE_OR, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_in_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_inclusive_or_expression ();
		while (accept (TokenType.IN)) {
			var right = parse_inclusive_or_expression ();
			left = new BinaryExpression (BinaryOperator.IN, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_conditional_and_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_in_expression ();
		while (accept (TokenType.OP_AND)) {
			var right = parse_in_expression ();
			left = new BinaryExpression (BinaryOperator.AND, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_conditional_or_expression () throws ParseError {
		var begin = get_location ();
		var left = parse_conditional_and_expression ();
		while (accept (TokenType.OP_OR)) {
			var right = parse_conditional_and_expression ();
			left = new BinaryExpression (BinaryOperator.OR, left, right, get_src (begin));
		}
		return left;
	}

	Expression parse_conditional_expression () throws ParseError {
		var begin = get_location ();
		var condition = parse_conditional_or_expression ();
		if (accept (TokenType.INTERR)) {
			var true_expr = parse_expression ();
			expect (TokenType.COLON);
			var false_expr = parse_expression ();
			return new ConditionalExpression (condition, true_expr, false_expr, get_src (begin));
		} else {
			return condition;
		}
	}

	Parameter parse_lambda_parameter () throws ParseError {
		var begin = get_location ();
		var direction = ParameterDirection.IN;
		if (accept (TokenType.OUT)) {
			direction = ParameterDirection.OUT;
		} else if (accept (TokenType.REF)) {
			direction = ParameterDirection.REF;
		}

		string id = parse_identifier ();

		var param = new Parameter (id, null, get_src (begin));
		param.direction = direction;
		return param;
	}

	Expression parse_lambda_expression () throws ParseError {
		var begin = get_location ();
		List<Parameter> params = new ArrayList<Parameter> ();

		expect (TokenType.DEF);

		if (accept (TokenType.OPEN_PARENS)) {
			if (current () != TokenType.CLOSE_PARENS) {
				do {
					params.add (parse_lambda_parameter ());
				} while (accept (TokenType.COMMA));
			}
			expect (TokenType.CLOSE_PARENS);
		} else {
			params.add (parse_lambda_parameter ());
		}

		LambdaExpression lambda;

		if (accept_block ()) {
			var block = parse_block ();
			lambda = new LambdaExpression.with_statement_body (block, get_src (begin));
		} else {
			var expr = parse_expression ();
			lambda = new LambdaExpression (expr, get_src (begin));
			expect_terminator ();

		}


		foreach (var param in params) {
			lambda.add_parameter (param);
		}
		return lambda;
	}

	AssignmentOperator get_assignment_operator (TokenType token_type) {
		switch (token_type) {
		case TokenType.ASSIGN:				return AssignmentOperator.SIMPLE;
		case TokenType.ASSIGN_ADD:			return AssignmentOperator.ADD;
		case TokenType.ASSIGN_SUB:			return AssignmentOperator.SUB;
		case TokenType.ASSIGN_BITWISE_OR:	return AssignmentOperator.BITWISE_OR;
		case TokenType.ASSIGN_BITWISE_AND:	return AssignmentOperator.BITWISE_AND;
		case TokenType.ASSIGN_BITWISE_XOR:	return AssignmentOperator.BITWISE_XOR;
		case TokenType.ASSIGN_DIV:			return AssignmentOperator.DIV;
		case TokenType.ASSIGN_MUL:			return AssignmentOperator.MUL;
		case TokenType.ASSIGN_PERCENT:		return AssignmentOperator.PERCENT;
		case TokenType.ASSIGN_SHIFT_LEFT:	return AssignmentOperator.SHIFT_LEFT;
		default:							return AssignmentOperator.NONE;
		}
	}

	Expression parse_expression_with_terminator () throws ParseError {
		var expr = parse_expression ();
		if (current_expr_is_lambda) {
			current_expr_is_lambda = false;
		} else {
			expect_terminator ();
		}
		return expr;
	}

	Expression parse_expression () throws ParseError {
		if (current () == TokenType.DEF) {
			var lambda = parse_lambda_expression ();
			current_expr_is_lambda = true;
			return lambda;
		} else {
			current_expr_is_lambda = false;
		}

		var begin = get_location ();
		Expression expr = parse_conditional_expression ();

		while (true) {
			var operator = get_assignment_operator (current ());
			if (operator != AssignmentOperator.NONE) {
				next ();
				var rhs = parse_expression ();
				expr = new Assignment (expr, rhs, operator, get_src (begin));
			} else if (current () == TokenType.OP_GT) { // >>=
				char* first_gt_pos = tokens[index].begin.pos;
				next ();
				// only accept >>= when there is no space between the two > signs
				if (current () == TokenType.OP_GE && tokens[index].begin.pos == first_gt_pos + 1) {
					next ();
					var rhs = parse_expression ();
					expr = new Assignment (expr, rhs, AssignmentOperator.SHIFT_RIGHT, get_src (begin));
				} else {
					prev ();
					break;
				}
			} else {
				break;
			}
		}

		return expr;
	}


	Statement get_for_statement_type () throws ParseError {

		var begin = get_location ();
		bool is_foreach = false;

		while (current () != TokenType.EOL && current () != TokenType.DO) {
			next ();
			if (accept (TokenType.IN)) {
				is_foreach = true;
				break;
			}
		}

		rollback (begin);

		if (is_foreach) {
			return parse_foreach_statement ();
		} else {
			return parse_for_statement ();
		}

	}

	void parse_statements (Block block) throws ParseError {
		while (current () != TokenType.DEDENT
			   && current () != TokenType.WHEN
			   && current () != TokenType.DEFAULT) {
			try {
				Statement stmt = null;
				bool is_decl = false;
				comment = scanner.pop_comment ();
				switch (current ()) {

				/* skip over requires and ensures as we handled them in method declaration */
				case TokenType.REQUIRES:
				case TokenType.ENSURES:
					var begin = get_location ();
					next ();

					if (accept (TokenType.EOL) && accept (TokenType.INDENT)) {
						while (current () != TokenType.DEDENT) {
							next();
						}

						expect (TokenType.DEDENT);
					} else {
						while (current () != TokenType.EOL) {
							next();
						}

						expect (TokenType.EOL);
					}

					stmt =  new EmptyStatement (get_src (begin));
					break;


				case TokenType.INDENT:
					stmt = parse_block ();
					break;
				case TokenType.SEMICOLON:
				case TokenType.PASS:
					stmt = parse_empty_statement ();
					break;
				case TokenType.PRINT:
				case TokenType.ASSERT:
					stmt = parse_expression_statement ();
					break;
				case TokenType.IF:
					stmt = parse_if_statement ();
					break;
				case TokenType.CASE:
					stmt = parse_switch_statement ();
					break;
				case TokenType.WHILE:
					stmt = parse_while_statement ();
					break;
				case TokenType.DO:
					stmt = parse_do_statement ();
					break;
				case TokenType.FOR:
					stmt = get_for_statement_type ();
					break;
				case TokenType.BREAK:
					stmt = parse_break_statement ();
					break;
				case TokenType.CONTINUE:
					stmt = parse_continue_statement ();
					break;
				case TokenType.RETURN:
					stmt = parse_return_statement ();
					break;
				case TokenType.RAISE:
					stmt = parse_throw_statement ();
					break;
				case TokenType.TRY:
					stmt = parse_try_statement ();
					break;
				case TokenType.LOCK:
					stmt = parse_lock_statement ();
					break;
				case TokenType.DELETE:
					stmt = parse_delete_statement ();
					break;
				case TokenType.VAR:
					is_decl = true;
					parse_type_inference_declaration (block);
					break;
				case TokenType.YIELD:
					stmt = parse_yield_statement ();
					break;

				case TokenType.OP_INC:
				case TokenType.OP_DEC:
				case TokenType.SUPER:
				case TokenType.SELF:
				case TokenType.OPEN_PARENS:
				case TokenType.STAR:
				case TokenType.NEW:
					stmt = parse_expression_statement ();
					break;
				default:
					bool is_expr = is_expression ();
					if (is_expr) {
						stmt = parse_expression_statement ();
					} else {
						is_decl = true;
						parse_local_variable_declarations (block);
					}
					break;
				}

				if (!is_decl) {
					block.add_statement (stmt);
				}
			} catch (ParseError e) {
				report_parse_error (e);
				if (recover () != RecoveryState.STATEMENT_BEGIN) {
					// beginning of next declaration or end of file reached
					// return what we have so far
					break;
				}
			}
		}
	}

	bool is_expression () throws ParseError {
		var begin = get_location ();

		// decide between declaration and expression statement
		skip_type ();
		switch (current ()) {
		// invocation expression
		case TokenType.OPEN_PARENS:
		// postfix increment
		case TokenType.OP_INC:
		// postfix decrement
		case TokenType.OP_DEC:
		// assignments
		case TokenType.ASSIGN:
		case TokenType.ASSIGN_ADD:
		case TokenType.ASSIGN_BITWISE_AND:
		case TokenType.ASSIGN_BITWISE_OR:
		case TokenType.ASSIGN_BITWISE_XOR:
		case TokenType.ASSIGN_DIV:
		case TokenType.ASSIGN_MUL:
		case TokenType.ASSIGN_PERCENT:
		case TokenType.ASSIGN_SHIFT_LEFT:
		case TokenType.ASSIGN_SUB:
		case TokenType.OP_GT: // >>=
		// member access
		case TokenType.DOT:
		// pointer member access
		case TokenType.OP_PTR:
			rollback (begin);
			return true;
		default:
			rollback (begin);
			return false;
		}
	}

	Block parse_embedded_statement () throws ParseError {
		if (current () == TokenType.INDENT) {
			var block = parse_block ();
			return block;
		}

		comment = scanner.pop_comment ();

		var block = new Block (get_src (get_location ()));
		block.add_statement (parse_embedded_statement_without_block ());
		return block;

	}

	Statement parse_embedded_statement_without_block () throws ParseError {
		switch (current ()) {
		case TokenType.PASS:
		case TokenType.SEMICOLON: return parse_empty_statement ();
		case TokenType.IF:		return parse_if_statement ();
		case TokenType.CASE:	  return parse_switch_statement ();
		case TokenType.WHILE:	 return parse_while_statement ();
		case TokenType.DO:		return parse_do_statement ();
		case TokenType.FOR:	   return get_for_statement_type ();
		case TokenType.BREAK:	 return parse_break_statement ();
		case TokenType.CONTINUE:  return parse_continue_statement ();
		case TokenType.RETURN:	return parse_return_statement ();
		case TokenType.YIELD:	 return parse_yield_statement ();
		case TokenType.RAISE:	 return parse_throw_statement ();
		case TokenType.TRY:	   return parse_try_statement ();
		case TokenType.LOCK:	  return parse_lock_statement ();
		case TokenType.DELETE:	return parse_delete_statement ();
		case TokenType.VAR:
		case TokenType.CONST:
			throw new ParseError.SYNTAX ("embedded statement cannot be declaration ");
		case TokenType.OP_INC:
		case TokenType.OP_DEC:
		case TokenType.SUPER:
		case TokenType.SELF:
		case TokenType.OPEN_PARENS:
		case TokenType.STAR:
		case TokenType.NEW:
			return parse_expression_statement ();
		default:
			if (is_expression ()) {
				return parse_expression_statement ();
			} else {
				throw new ParseError.SYNTAX ("embedded statement cannot be declaration");
			}
		}
	}

	Block parse_block () throws ParseError {
		var begin = get_location ();
		expect (TokenType.INDENT);
		var block = new Block (get_src (begin));
		parse_statements (block);
		if (!accept (TokenType.DEDENT)) {
			// only report error if it's not a secondary error
			if (context.report.get_errors () == 0) {
				Report.error (get_current_src (), "tab indentation is incorrect");
			}
		}

		block.source_reference.end = get_current_src ().end;

		return block;
	}

	Statement parse_empty_statement () throws ParseError {
		var begin = get_location ();

		accept (TokenType.PASS);
		accept (TokenType.SEMICOLON);
		expect_terminator ();

		return new EmptyStatement (get_src (begin));
	}

	void parse_type_inference_declaration (Block block)  throws ParseError {
		expect (TokenType.VAR);
		bool block_var = false;
		if (accept (TokenType.EOL) && accept (TokenType.INDENT)) { block_var = true; }
		do {
			var s = parse_identifier ();
			var local = parse_local_variable (null, s, true);
			block.add_statement (new DeclarationStatement (local, local.source_reference));
		}
		while ((block_var) && (current () != TokenType.DEDENT));
		if ( block_var ) { expect (TokenType.DEDENT); }
	}

	void parse_local_variable_declarations (Block block) throws ParseError {
		var id_list = new ArrayList<string> (str_equal);
		id_list.add (parse_identifier ());
		// Allow multiple declarations
		while (accept (TokenType.COMMA)) {
			id_list.add (parse_identifier ());
		}

		expect (TokenType.COLON);
		DataType variable_type = parse_type (true, true);
		var type = parse_inline_array_type (variable_type);

		var iterator = id_list.iterator();
		iterator.next();
		bool expect_terminator = false;
		while (!expect_terminator) {
			string id = iterator.get();
			DataType type_copy = null;
			if (type != null) {
				type_copy = type.copy ();
			}
			if (!iterator.next()) {
				expect_terminator = true;
			}
			var local = parse_local_variable (type_copy, id, expect_terminator);
			block.add_statement (new DeclarationStatement (local, local.source_reference));
		}
	}

	LocalVariable parse_local_variable (DataType? variable_type, string id, bool expect_terminator = false) throws ParseError {
		var begin = get_location ();
		Expression initializer = null;
		if (accept (TokenType.ASSIGN)) {
			if (expect_terminator) {
				initializer = parse_expression_with_terminator ();
			} else {
				initializer = parse_expression ();
			}
		} else if (expect_terminator) {
			this.expect_terminator();
			}
		return new LocalVariable (variable_type, id, initializer, get_src (begin));
	}

	Statement parse_expression_statement () throws ParseError {
		var begin = get_location ();
		var expr = parse_expression_with_terminator ();
		return new ExpressionStatement (expr, get_src (begin));
	}

	Expression parse_statement_expression () throws ParseError {
		// invocation expression, assignment,
		// or pre/post increment/decrement expression
		var expr = parse_expression ();
		return expr;
	}

	Statement parse_if_statement () throws ParseError {
		var begin = get_location ();

		expect (TokenType.IF);

		var condition = parse_expression ();

		if (!accept (TokenType.DO)) {
			expect (TokenType.EOL);
		} else {
			accept (TokenType.EOL);
		}

		var src = get_src (begin);
		var true_stmt = parse_embedded_statement ();
		Block false_stmt = null;
		if (accept (TokenType.ELSE)) {
			// allow `else if' on the same line without `do'
			if (!accept (TokenType.DO) && current () != TokenType.IF) {
				expect (TokenType.EOL);
			} else {
				accept (TokenType.EOL);
			}

			false_stmt = parse_embedded_statement ();
		}
		return new IfStatement (condition, true_stmt, false_stmt, src);
	}

	Statement parse_switch_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.CASE);
		var condition = parse_expression ();

		expect (TokenType.EOL);

		var stmt = new SwitchStatement (condition, get_src (begin));
		expect (TokenType.INDENT);
		while (current () != TokenType.DEDENT) {
			var section = new SwitchSection (get_src (begin));

			if (accept (TokenType.WHEN)) {
				do {
					section.add_label (new SwitchLabel (parse_expression (), get_src (begin)));
				}
				while (accept (TokenType.COMMA));
			} else {
				expect (TokenType.DEFAULT);
				section.add_label (new SwitchLabel.with_default (get_src (begin)));
			}

			if (!accept (TokenType.EOL)) {
				expect (TokenType.DO);
			}

			parse_statements (section);

			/* add break statement for each block */
			var break_stmt =  new BreakStatement (get_src (begin));
			section.add_statement (break_stmt);

			stmt.add_section (section);
		}
		expect (TokenType.DEDENT);
		return stmt;
	}

	Statement parse_while_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.WHILE);
		var condition = parse_expression ();

		if (!accept (TokenType.DO)) {
			expect (TokenType.EOL);
		} else {
			accept (TokenType.EOL);
		}

		var body = parse_embedded_statement ();
		return new WhileStatement (condition, body, get_src (begin));
	}

	Statement parse_do_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.DO);
		expect (TokenType.EOL);
		var body = parse_embedded_statement ();
		expect (TokenType.WHILE);

		var condition = parse_expression ();

		expect_terminator ();

		return new DoStatement (condition, body, get_src (begin));
	}


	Statement parse_for_statement () throws ParseError {
		var begin = get_location ();
		Block block = null;
		Expression initializer = null;
		Expression condition = null;
		Expression iterator = null;
		bool is_expr;
		string id;

		expect (TokenType.FOR);

		switch (current ()) {
		case TokenType.VAR:
			is_expr = false;
			break;
		default:

			bool local_is_expr = is_expression ();
			is_expr = local_is_expr;
			break;
		}

		if (is_expr) {
			var expr_begin = get_location ();
			id = parse_identifier ();
			rollback (expr_begin);
			initializer = parse_statement_expression ();
		} else {
			block = new Block (get_src (begin));
			DataType variable_type;
			if (accept (TokenType.VAR)) {
				variable_type = null;
				id = parse_identifier ();
			} else {
				id = parse_identifier ();
				expect (TokenType.COLON);
				variable_type = parse_type (true, true);
			}

			DataType type_copy = null;
			if (variable_type != null) {
				type_copy = variable_type.copy ();
			}
			var local = parse_local_variable (type_copy, id);

			block.add_statement (new DeclarationStatement (local, local.source_reference));
		}



		if (accept (TokenType.TO)) {
			/* create expression for condition and incrementing iterator */
			var to_begin = get_location ();
			var to_src = get_src (to_begin);
			var left = new MemberAccess (null, id, to_src);
			var right = parse_primary_expression ();

			condition = new BinaryExpression (BinaryOperator.LESS_THAN_OR_EQUAL, left, right, to_src);

			iterator = new PostfixExpression (left, true, to_src);
		} else {
			expect (TokenType.DOWNTO);
			var downto_begin = get_location ();
			var downto_src = get_src (downto_begin);
			/* create expression for condition and decrementing iterator */
			var left = new MemberAccess (null, id, downto_src);
			var right = parse_primary_expression ();

			condition = new BinaryExpression (BinaryOperator.GREATER_THAN_OR_EQUAL, left, right, downto_src);

			iterator = new PostfixExpression (left, false, downto_src);
		}

		if (!accept (TokenType.EOL)) {
			expect (TokenType.DO);
		}

		var src = get_src (begin);
		var body = parse_embedded_statement ();
		var stmt = new ForStatement (condition, body, src);

		if (initializer != null) stmt.add_initializer (initializer);

		stmt.add_iterator (iterator);


		if (block != null) {
			block.add_statement (stmt);
			return block;
		} else {
			return stmt;
		}
	}

	Statement parse_foreach_statement () throws ParseError {
		var begin = get_location ();
		DataType type = null;
		string id = null;

		expect (TokenType.FOR);

		if (accept (TokenType.VAR)) {
			 id = parse_identifier ();
		} else {
			id = parse_identifier ();
			if (accept (TokenType.COLON)) {
				type = parse_type (true, true);
			}
		}

		expect (TokenType.IN);
		var collection = parse_expression ();
		if (!accept (TokenType.EOL)) {
			expect (TokenType.DO);
		}
		var src = get_src (begin);
		var body = parse_embedded_statement ();
		return new ForeachStatement (type, id, collection, body, src);
	}

	Statement parse_break_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.BREAK);
		expect_terminator ();
		return new BreakStatement (get_src (begin));
	}

	Statement parse_continue_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.CONTINUE);
		expect_terminator ();
		return new ContinueStatement (get_src (begin));
	}

	Statement parse_return_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.RETURN);
		Expression expr = null;
		if (current () != TokenType.SEMICOLON && current () != TokenType.EOL) {
			expr = parse_expression_with_terminator ();
		} else {
			expect_terminator ();
		}
		return new ReturnStatement (expr, get_src (begin));
	}

	Statement parse_yield_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.YIELD);
		if (current () != TokenType.SEMICOLON && current () != TokenType.EOL) {
			prev ();
			return parse_expression_statement ();
		}
		expect_terminator ();
		return new YieldStatement (get_src (begin));
	}

	Statement parse_throw_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.RAISE);
		var expr = parse_expression ();
		expect_terminator ();
		return new ThrowStatement (expr, get_src (begin));
	}

	Statement parse_try_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.TRY);
		expect (TokenType.EOL);
		var try_block = parse_block ();
		Block finally_clause = null;
		var catch_clauses = new ArrayList<CatchClause> ();
		if (current () == TokenType.EXCEPT) {
			parse_catch_clauses (catch_clauses);
			if (current () == TokenType.FINALLY) {
				finally_clause = parse_finally_clause ();
			}
		} else {
			finally_clause = parse_finally_clause ();
		}
		var stmt = new TryStatement (try_block, finally_clause, get_src (begin));
		foreach (CatchClause clause in catch_clauses) {
			stmt.add_catch_clause (clause);
		}
		return stmt;
	}

	void parse_catch_clauses (List<CatchClause> catch_clauses) throws ParseError {
		while (accept (TokenType.EXCEPT)) {
			var begin = get_location ();
			DataType type = null;
			string id = null;
			if (!accept (TokenType.EOL)) {
				id = parse_identifier ();
				expect (TokenType.COLON);
				type = parse_type (true, true);
				expect (TokenType.EOL);

			}
			var block = parse_block ();
			catch_clauses.add (new CatchClause (type, id, block, get_src (begin)));
		}
	}

	Block parse_finally_clause () throws ParseError {
		expect (TokenType.FINALLY);
		accept_block ();
		var block = parse_block ();
		return block;
	}

	Statement parse_lock_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.LOCK);
		expect (TokenType.OPEN_PARENS);
		var expr = parse_expression ();
		expect (TokenType.CLOSE_PARENS);
		var stmt = parse_embedded_statement ();
		return new LockStatement (expr, stmt, get_src (begin));
	}

	Statement parse_delete_statement () throws ParseError {
		var begin = get_location ();
		expect (TokenType.DELETE);
		var expr = parse_expression ();
		expect_terminator ();
		return new DeleteStatement (expr, get_src (begin));
	}

	string parse_attribute_value () throws ParseError {
		switch (current ()) {
		case TokenType.NULL:
		case TokenType.TRUE:
		case TokenType.FALSE:
		case TokenType.INTEGER_LITERAL:
		case TokenType.REAL_LITERAL:
		case TokenType.STRING_LITERAL:
			next ();
			return get_last_string ();
		case TokenType.MINUS:
			next ();
			switch (current ()) {
			case TokenType.INTEGER_LITERAL:
			case TokenType.REAL_LITERAL:
				next ();
				return "-" + get_last_string ();
			default:
				throw new ParseError.SYNTAX ("expected number");
			}
		default:
			throw new ParseError.SYNTAX ("expected literal");
		}
	}

	List<Attribute>? parse_attributes (bool parameter) throws ParseError {
		if (current () != TokenType.OPEN_BRACKET) {
			return null;
		}
		var attrs = new ArrayList<Attribute> ();
		while (accept (TokenType.OPEN_BRACKET)) {
			do {
				var begin = get_location ();
				string id = parse_identifier ();
				var attr = new Attribute (id, get_src (begin));
				if (accept (TokenType.OPEN_PARENS)) {
					if (current () != TokenType.CLOSE_PARENS) {
						do {
							id = parse_identifier ();
							expect (TokenType.ASSIGN);
							attr.add_argument (id, parse_attribute_value ());
						} while (accept (TokenType.COMMA));
					}
					expect (TokenType.CLOSE_PARENS);
				}
				attrs.add (attr);
			} while (accept (TokenType.COMMA));
			expect (TokenType.CLOSE_BRACKET);
		}
		if (!parameter)
			expect (TokenType.EOL);
		return attrs;
	}

	void set_attributes (CodeNode node, List<Attribute>? attributes) {
		if (attributes != null) {
			foreach (Attribute attr in (List<Attribute>) attributes) {
				if (node.get_attribute (attr.name) != null) {
					Report.error (attr.source_reference, "duplicate attribute `%s'", attr.name);
				}
				node.attributes.append (attr);
			}
		}
	}

	Symbol parse_declaration (bool is_root = false) throws ParseError {
		comment = scanner.pop_comment ();
		var attrs = parse_attributes (false);
		var begin = get_location ();

		switch (current ()) {
		case TokenType.CONST:
			return parse_constant_declaration (attrs);
		case TokenType.CONSTRUCT:
			return parse_creation_method_declaration (attrs);
		case TokenType.CLASS:
			return parse_class_declaration (attrs);
		case TokenType.INIT:
			if (is_root) {
				return parse_main_method_declaration (attrs);
			}
			if (context.profile == Profile.GOBJECT) {
				rollback (begin);
				return parse_constructor_declaration (attrs);
			}
			break;
		case TokenType.DELEGATE:
			return parse_delegate_declaration (attrs);
		case TokenType.DEF:
			return parse_method_declaration (attrs);
		case TokenType.ENUM:
			return parse_enum_declaration (attrs);
		case TokenType.EXCEPTION:
			return parse_errordomain_declaration (attrs);
		case TokenType.FINAL:
			return parse_destructor_declaration (attrs);
		case TokenType.INTERFACE:
			return parse_interface_declaration (attrs);
		case TokenType.NAMESPACE:
			return parse_namespace_declaration (attrs);
		case TokenType.PROP:
			return parse_property_declaration (attrs);
		case TokenType.EVENT:
			return parse_signal_declaration (attrs);
		case TokenType.STRUCT:
			return parse_struct_declaration (attrs);
		default:

			while (current () != TokenType.EOL && current () != TokenType.SEMICOLON && current () != TokenType.EOF) {
				if (current () == TokenType.COLON) {
					rollback (begin);
					return parse_field_declaration (attrs);
				} else {
					next ();
				}
			}
			rollback (begin);

			break;
		}

		TokenType cur = current ();
		TokenType pre =  tokens[index-1].type;

		throw new ParseError.SYNTAX ("expected a declaration after %s, but got %s", pre.to_string (), cur.to_string());
	}

	void parse_declarations (Symbol parent, bool root = false) throws ParseError {
		if (!root) {
			expect (TokenType.INDENT);
		}
		while (current () != TokenType.DEDENT && current () != TokenType.EOF) {
			try {
				if (parent is Namespace) {
					parse_namespace_member ((Namespace) parent);
				} else if (parent is Class) {
					parse_class_member ((Class) parent);
				} else if (parent is Struct) {
					parse_struct_member ((Struct) parent);
				} else if (parent is Interface) {
					parse_interface_member ((Interface) parent);
				}
			} catch (ParseError e) {
				report_parse_error (e);
				int r;
				do {
					r = recover ();
					if (r == RecoveryState.STATEMENT_BEGIN) {
						next ();
					} else {
						break;
					}
				} while (true);
				if (r == RecoveryState.EOF) {
					return;
				}
			}
		}
		if (!root) {
			if (!accept (TokenType.DEDENT)) {
				// only report error if it's not a secondary error
				if (context.report.get_errors () == 0) {
					Report.error (get_current_src (), "expected dedent");
				}
			}
		}
	}

	enum RecoveryState {
		EOF,
		DECLARATION_BEGIN,
		STATEMENT_BEGIN
	}

	RecoveryState recover () {
		while (current () != TokenType.EOF) {
			switch (current ()) {
			case TokenType.CLASS:
			case TokenType.CONST:
			case TokenType.CONSTRUCT:
			case TokenType.INIT:
			case TokenType.DEF:
			case TokenType.DELEGATE:
			case TokenType.ENUM:
			case TokenType.EXCEPTION:
			case TokenType.FINAL:
			case TokenType.INTERFACE:
			case TokenType.NAMESPACE:
			case TokenType.PROP:
			case TokenType.EVENT:
			case TokenType.STRUCT:
				return RecoveryState.DECLARATION_BEGIN;
			case TokenType.BREAK:
			case TokenType.CASE:
			case TokenType.CONTINUE:
			case TokenType.DELETE:
			case TokenType.DO:
			case TokenType.FOR:
			case TokenType.IF:
			case TokenType.LOCK:
			case TokenType.RETURN:
			case TokenType.RAISE:
			case TokenType.TRY:
			case TokenType.VAR:
			case TokenType.WHILE:
			case TokenType.YIELD:
				return RecoveryState.STATEMENT_BEGIN;
			default:
				next ();
				break;
			}
		}
		return RecoveryState.EOF;
	}

	Namespace parse_namespace_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		expect (TokenType.NAMESPACE);
		var sym = parse_symbol_name ();
		var ns = new Namespace (sym.name, get_src (begin));
		if (comment != null) {
			ns.add_comment (comment);
			comment = null;
		}
		set_attributes (ns, attrs);
		expect (TokenType.EOL);
		parse_declarations (ns);

		Namespace result = ns;
		while (sym.inner != null) {
			sym = sym.inner;
			ns = new Namespace (sym.name, result.source_reference);
			ns.add_namespace ((Namespace) result);
			result = ns;
		}
		return result;
	}

	void parse_namespace_member (Namespace ns) throws ParseError {

		var sym = parse_declaration ((ns == context.root));
		if (sym is Namespace) {
			ns.add_namespace ((Namespace) sym);
		} else if (sym is Class) {
			ns.add_class ((Class) sym);
		} else if (sym is Interface) {
			ns.add_interface ((Interface) sym);
		} else if (sym is Struct) {
			ns.add_struct ((Struct) sym);
		} else if (sym is Enum) {
			ns.add_enum ((Enum) sym);
		} else if (sym is ErrorDomain) {
			ns.add_error_domain ((ErrorDomain) sym);
		} else if (sym is Delegate) {
			ns.add_delegate ((Delegate) sym);
		} else if (sym is Method) {
			unowned Method method = (Method) sym;
			if (method.binding == MemberBinding.INSTANCE) {
				method.binding = MemberBinding.STATIC;
			}
			ns.add_method (method);
		} else if (sym is Field) {
			unowned Field field = (Field) sym;
			if (field.binding == MemberBinding.INSTANCE) {
				field.binding = MemberBinding.STATIC;
			}
			ns.add_field (field);
		} else if (sym is Constant) {
			ns.add_constant ((Constant) sym);
		} else {
			Report.error (sym.source_reference, "unexpected declaration in namespace");
		}
	}


	void add_uses_clause (Namespace ns) throws ParseError {
		var begin = get_location ();
		var sym = parse_symbol_name ();
		var ns_ref = new UsingDirective (sym, get_src (begin));

		scanner.source_file.add_using_directive (ns_ref);
		ns.add_using_directive (ns_ref);
	}

	void parse_using_directives (Namespace ns) throws ParseError {
		while (accept (TokenType.USES)) {
			if (accept_block ()) {
				expect (TokenType.INDENT);

				while (current () != TokenType.DEDENT && current () != TokenType.EOF) {
					add_uses_clause (ns);
					expect (TokenType.EOL);
				}

				expect (TokenType.DEDENT);
			} else {
				do {
					add_uses_clause (ns);
				} while (accept (TokenType.COMMA));

				expect_terminator ();
			}
		}

	}

	Symbol parse_class_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		expect (TokenType.CLASS);

		var flags = parse_type_declaration_modifiers ();

		var sym = parse_symbol_name ();
		var type_param_list = parse_type_parameter_list ();
		var base_types = new ArrayList<DataType> ();
		if (accept (TokenType.COLON)) {
			var type1 = parse_type (true, false);
			base_types.add (type1);

			if (accept (TokenType.IMPLEMENTS)) {
				do {
					var type2 = parse_type (true, true);
					base_types.add (type2);
				} while (accept (TokenType.COMMA));
			}
		}

		accept (TokenType.EOL);

		var cl = new Class (sym.name, get_src (begin), comment);

		if (ModifierFlags.PRIVATE in flags) {
			cl.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			cl.access = SymbolAccessibility.PROTECTED;
		} else {
			cl.access = get_default_accessibility (sym.name);
		}

		if (ModifierFlags.ABSTRACT in flags) {
			cl.is_abstract = true;
		}
		set_attributes (cl, attrs);
		foreach (TypeParameter type_param in type_param_list) {
			cl.add_type_parameter (type_param);
		}
		foreach (DataType base_type in base_types) {
			cl.add_base_type (base_type);
		}

		class_name = cl.name;

		parse_declarations (cl);

		// ensure there is always a default construction method
		if (scanner.source_file.file_type == SourceFileType.SOURCE
			&& cl.default_construction_method == null) {
			var m = new CreationMethod (cl.name, null, cl.source_reference);
			m.access = (cl.is_abstract ? SymbolAccessibility.PROTECTED : SymbolAccessibility.PUBLIC);
			m.body = new Block (cl.source_reference);
			cl.add_method (m);
		}

		Symbol result = cl;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, cl.source_reference);
			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_class ((Class) result);
			}
			result = ns;
		}
		return result;
	}

	void parse_class_member (Class cl) throws ParseError {
		var sym = parse_declaration ();
		if (sym is Class) {
			cl.add_class ((Class) sym);
		} else if (sym is Struct) {
			cl.add_struct ((Struct) sym);
		} else if (sym is Enum) {
			cl.add_enum ((Enum) sym);
		} else if (sym is Delegate) {
			cl.add_delegate ((Delegate) sym);
		} else if (sym is Method) {
			cl.add_method ((Method) sym);
		} else if (sym is Vala.Signal) {
			cl.add_signal ((Vala.Signal) sym);
		} else if (sym is Field) {
			cl.add_field ((Field) sym);
		} else if (sym is Constant) {
			cl.add_constant ((Constant) sym);
		} else if (sym is Property) {
			cl.add_property ((Property) sym);
		} else if (sym is Constructor) {
			cl.add_constructor ((Constructor) sym);
		} else if (sym is Destructor) {
			cl.add_destructor ((Destructor) sym);
		} else {
			Report.error (sym.source_reference, "unexpected declaration in class");
		}
	}

	Constant parse_constant_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();

		expect (TokenType.CONST);

		var flags = parse_member_declaration_modifiers ();

		string id = parse_identifier ();

		expect (TokenType.COLON);
		var type = parse_type (false, false);
		type = parse_inline_array_type (type);

		Expression initializer = null;
		if (accept (TokenType.ASSIGN)) {
			initializer = parse_expression ();
		}
		expect_terminator ();

		// constant arrays don't own their element
		unowned ArrayType? array_type = type as ArrayType;
		if (array_type != null) {
			array_type.element_type.value_owned = false;
		}

		var c = new Constant (id, type, initializer, get_src (begin), comment);
		c.access = get_default_accessibility (id);

		if (ModifierFlags.EXTERN in flags) {
			c.is_extern = true;
		}
		if (ModifierFlags.NEW in flags) {
			c.hides = true;
		}

		set_attributes (c, attrs);

		if (ModifierFlags.STATIC in flags) {
			Report.warning (c.source_reference, "the modifier `static' is not applicable to constants");
		}

		return c;
	}

	Field parse_field_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		string id = parse_identifier ();
		expect (TokenType.COLON);

		var flags = parse_member_declaration_modifiers ();

		var type = parse_type (true, true);

		type = parse_inline_array_type (type);

		var f = new Field (id, type, null, get_src (begin), comment);

		if (ModifierFlags.ABSTRACT in flags || ModifierFlags.VIRTUAL in flags || ModifierFlags.OVERRIDE in flags) {
			Report.error (f.source_reference, "abstract, virtual, and override modifiers are not applicable to fields");
		}

		if (ModifierFlags.PRIVATE in flags) {
			f.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			f.access = SymbolAccessibility.PROTECTED;
		} else {
			f.access = get_default_accessibility (id);
		}

		set_attributes (f, attrs);

		if (ModifierFlags.EXTERN in flags) {
			f.is_extern = true;
		}
		if (ModifierFlags.NEW in flags) {
			f.hides = true;
		}

		if (accept (TokenType.ASSIGN)) {
			f.initializer = parse_expression ();
		}

		if (ModifierFlags.STATIC in flags) {
			f.binding = MemberBinding.STATIC;
		} else if (ModifierFlags.CLASS in flags) {
			f.binding = MemberBinding.CLASS;
		}

		expect_terminator ();

		return f;
	}

	InitializerList parse_initializer () throws ParseError {
		var begin = get_location ();
		if  (!accept (TokenType.OPEN_PARENS)) {
			expect (TokenType.OPEN_BRACE);
		}
		var initializer = new InitializerList (get_src (begin));
		if (current () != TokenType.DEDENT) {
			do {
				var init = parse_argument ();
				initializer.append (init);
			} while (accept (TokenType.COMMA));
		}
		if  (!accept (TokenType.CLOSE_PARENS)) {
			expect (TokenType.CLOSE_BRACE);
		}
		return initializer;
	}




	Method parse_main_method_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		DataType type;

		expect (TokenType.INIT);

		if (accept (TokenType.COLON)) {
			type = parse_type (true, false);
			if (type.to_string () != "int") {
				throw new ParseError.SYNTAX ("main `init' must return void or `int', but got `%s'".printf (type.to_string ()));
			}
		} else {
			type = new VoidType ();
		}

		var method = new Method ("main", type, get_src (begin), comment);
		method.access = SymbolAccessibility.PUBLIC;
		method.binding = MemberBinding.STATIC;
		set_attributes (method, attrs);

		var sym = new UnresolvedSymbol (null, "string", get_src (begin));
		type = new UnresolvedType.from_symbol (sym, get_src (begin));
		type.value_owned = true;
		type = new ArrayType (type, 1, get_src (begin));
		type.nullable = false;

		var param = new Parameter ("args", type, get_src (begin));
		method.add_parameter (param);


		expect (TokenType.EOL);

		if (accept_block ()) {
			method.body = parse_block ();
		}

		return method;
	}

	Method parse_method_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		DataType type;

		expect (TokenType.DEF);
		var flags = parse_member_declaration_modifiers ();

		string id = parse_identifier ();

		var params = new ArrayList<Parameter> ();
		expect (TokenType.OPEN_PARENS);

		if (current () != TokenType.CLOSE_PARENS) {
			do {
				var param = parse_parameter ();
				params.add (param);
			} while (accept (TokenType.COMMA));
		}

		expect (TokenType.CLOSE_PARENS);


		/* deal with return value */
		if (accept (TokenType.COLON)) {
			type = parse_type (true, false);
		} else {
			type = new VoidType ();
		}

		var type_param_list = parse_type_parameter_list ();

		var method = new Method (id, type, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			method.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			method.access = SymbolAccessibility.PROTECTED;
		} else {
			method.access = get_default_accessibility (id);
		}


		set_attributes (method, attrs);

		foreach (TypeParameter type_param in type_param_list) {
			method.add_type_parameter (type_param);
		}


		foreach (Parameter param in params) {
			method.add_parameter (param);
		}

		if (accept (TokenType.RAISES)) {
			do {
				method.add_error_type (parse_type (true, false));
			} while (accept (TokenType.COMMA));
		}


		if (ModifierFlags.STATIC in flags || id == "main") {
			method.binding = MemberBinding.STATIC;
		} else if (ModifierFlags.CLASS in flags) {
			method.binding = MemberBinding.CLASS;
		}
		if (ModifierFlags.ASYNC in flags) {
			method.coroutine = true;
		}

		if (ModifierFlags.NEW in flags) {
			method.hides = true;
		}

		if (method.binding == MemberBinding.INSTANCE) {
			if (ModifierFlags.ABSTRACT in flags) {
				method.is_abstract = true;
			}
			if (ModifierFlags.VIRTUAL in flags) {
				method.is_virtual = true;
			}
			if (ModifierFlags.OVERRIDE in flags) {
				method.overrides = true;
			}
			if ((method.is_abstract && method.is_virtual)
				|| (method.is_abstract && method.overrides)
				|| (method.is_virtual && method.overrides)) {
				throw new ParseError.SYNTAX ("only one of `abstract', `virtual', or `override' may be specified");
			}
		} else {
			if (ModifierFlags.ABSTRACT in flags
				|| ModifierFlags.VIRTUAL in flags
				|| ModifierFlags.OVERRIDE in flags) {
				throw new ParseError.SYNTAX ("the modifiers `abstract', `virtual', and `override' are not valid for static methods");
			}
		}

		if (ModifierFlags.INLINE in flags) {
			method.is_inline = true;
		}
		if (ModifierFlags.EXTERN in flags) {
			method.is_extern = true;
		}

		expect (TokenType.EOL);

		var body_location = get_location ();


		/* "requires" and "ensures" if present will be at  start of the method body */
		if (accept (TokenType.INDENT)) {
			if (accept (TokenType.REQUIRES)) {

				if (accept (TokenType.EOL) && accept (TokenType.INDENT)) {
					while (current() != TokenType.DEDENT) {
						method.add_precondition (parse_expression ());
						expect (TokenType.EOL);
					}

					expect (TokenType.DEDENT);
					accept_terminator ();
				} else {

					method.add_precondition (parse_expression ());
					expect_terminator ();

				}

			}

			if (accept (TokenType.ENSURES)) {
				if (accept (TokenType.EOL) && accept (TokenType.INDENT)) {
					while (current() != TokenType.DEDENT) {
						method.add_postcondition (parse_expression ());
						expect (TokenType.EOL);
					}

					expect (TokenType.DEDENT);
					accept_terminator ();
				} else {
					method.add_postcondition (parse_expression ());
					expect_terminator ();
				}
			}
		}

		rollback (body_location);


		if (accept_block ()) {
			method.body = parse_block ();
			method.external = false;
		}
		return method;
	}

	Property parse_property_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		var readonly = false;

		expect (TokenType.PROP);

		var flags = parse_member_declaration_modifiers ();

		readonly =  accept (TokenType.READONLY);

		string id = parse_identifier ();
		expect (TokenType.COLON);

		var type = parse_type (true, true);

		var prop = new Property (id, type, null, null, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			prop.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			prop.access = SymbolAccessibility.PROTECTED;
		} else {
			prop.access = get_default_accessibility (id);
		}

		set_attributes (prop, attrs);

		if (ModifierFlags.STATIC in flags) {
			prop.binding = MemberBinding.STATIC;
		} else if (ModifierFlags.CLASS in flags) {
			prop.binding = MemberBinding.CLASS;
		}
		if (ModifierFlags.ABSTRACT in flags) {
			prop.is_abstract = true;
		}
		if (ModifierFlags.VIRTUAL in flags) {
			prop.is_virtual = true;
		}
		if (ModifierFlags.OVERRIDE in flags) {
			prop.overrides = true;
		}

		if (ModifierFlags.NEW in flags) {
			prop.hides = true;
		}
		if (ModifierFlags.EXTERN in flags) {
			prop.is_extern = true;
		}

		if (ModifierFlags.ASYNC in flags) {
			Report.error (prop.source_reference, "async properties are not supported yet");
		}

		if (accept (TokenType.ASSIGN)) {
			prop.initializer = parse_expression ();
		}


		if (accept_block ()) {
			expect (TokenType.INDENT);
			while (current () != TokenType.DEDENT) {
				var accessor_begin = get_location ();
				var attribs = parse_attributes (false);

				var value_type = type.copy ();
				value_type.value_owned = accept (TokenType.OWNED);

				if (accept (TokenType.GET)) {
					if (prop.get_accessor != null) {
						throw new ParseError.SYNTAX ("property get accessor already defined");
					}
					Block block = null;
					if (accept_block ()) {
						block = parse_block ();
						prop.external = false;
					} else {
						accept (TokenType.EOL);
					}
					prop.get_accessor = new PropertyAccessor (true, false, false, value_type, block, get_src (accessor_begin));
					set_attributes (prop.get_accessor, attribs);
					prop.get_accessor.access = SymbolAccessibility.PUBLIC;
				} else {
					bool _construct = false;
					if (accept (TokenType.SET)) {
						if (readonly) {
							throw new ParseError.SYNTAX ("set block not allowed for a read only property");
						}
						_construct = (context.profile == Profile.GOBJECT) && accept (TokenType.CONSTRUCT);
					} else if (context.profile == Profile.GOBJECT && accept (TokenType.CONSTRUCT)) {
						_construct = true;
					} else if (!accept (TokenType.EOL)) {
						throw new ParseError.SYNTAX ("expected get, set, or construct");
					}

					if (prop.set_accessor != null) {
						throw new ParseError.SYNTAX ("property set accessor already defined");
					}

					Block block = null;
					if (accept_block ()) {
						block = parse_block ();
						prop.external = false;
					} else {
						accept (TokenType.EOL);
					}
					prop.set_accessor = new PropertyAccessor (false, !readonly, _construct, value_type, block, get_src (accessor_begin));
					set_attributes (prop.set_accessor, attribs);
					prop.set_accessor.access = SymbolAccessibility.PUBLIC;
				}
			}
			accept (TokenType.EOL);
			expect (TokenType.DEDENT);
		} else {
			var value_type = type.copy ();
			value_type.value_owned = false;

			prop.get_accessor = new PropertyAccessor (true, false, false, value_type, null, get_src (begin));
			prop.get_accessor.access = SymbolAccessibility.PUBLIC;

			if (!readonly) {
				value_type = type.copy ();
				value_type.value_owned = false;

				prop.set_accessor = new PropertyAccessor (false, true, false, value_type, null, get_src (begin));
				prop.set_accessor.access = SymbolAccessibility.PUBLIC;

			}

			expect_terminator ();
		}

		return prop;
	}

	Vala.Signal parse_signal_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		DataType type;

		expect (TokenType.EVENT);
		var flags = parse_member_declaration_modifiers ();
		string id = parse_identifier ();


		var params = new ArrayList<Parameter> ();

		expect (TokenType.OPEN_PARENS);
		if (current () != TokenType.CLOSE_PARENS) {
			do {
				var param = parse_parameter ();
				params.add (param);
			} while (accept (TokenType.COMMA));
		}
		expect (TokenType.CLOSE_PARENS);

		if (accept (TokenType.COLON)) {
			type = parse_type (true, false);
		} else {
			type = new VoidType ();
		}

		var sig = new Vala.Signal (id, type, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			sig.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			sig.access = SymbolAccessibility.PROTECTED;
		} else {
			sig.access = get_default_accessibility (id);
		}

		if (ModifierFlags.VIRTUAL in flags) {
			sig.is_virtual = true;
		}
		if (ModifierFlags.NEW in flags) {
			sig.hides = true;
		}

		if (ModifierFlags.STATIC in flags) {
			throw new ParseError.SYNTAX ("`static' modifier not allowed on signals");
		} else if (ModifierFlags.CLASS in flags) {
			throw new ParseError.SYNTAX ("`class' modifier not allowed on signals");
		}

		set_attributes (sig, attrs);

		foreach (Parameter formal_param in params) {
			sig.add_parameter (formal_param);
		}

		if (!accept_terminator ()) {
			sig.body = parse_block ();
		}
		return sig;
	}

	Constructor parse_constructor_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();

		expect (TokenType.INIT);
		var flags = parse_member_declaration_modifiers ();

		var c = new Constructor (get_src (begin));
		if (ModifierFlags.STATIC in flags) {
			c.binding = MemberBinding.STATIC;
		} else if (ModifierFlags.CLASS in flags) {
			c.binding = MemberBinding.CLASS;
		}

		accept_block ();
		c.body = parse_block ();
		return c;
	}

	Destructor parse_destructor_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		expect (TokenType.FINAL);
		var d = new Destructor (get_src (begin));
		accept_block ();
		d.body = parse_block ();
		return d;
	}

	Symbol parse_struct_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();

		expect (TokenType.STRUCT);
		var flags = parse_type_declaration_modifiers ();
		var sym = parse_symbol_name ();
		var type_param_list = parse_type_parameter_list ();
		DataType base_type = null;
		if (accept (TokenType.COLON)) {
			base_type = parse_type (true, false);
		}

		var st = new Struct (sym.name, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			st.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			st.access = SymbolAccessibility.PROTECTED;
		} else {
			st.access = get_default_accessibility (sym.name);
		}
		set_attributes (st, attrs);
		foreach (TypeParameter type_param in type_param_list) {
			st.add_type_parameter (type_param);
		}
		if (base_type != null) {
			st.base_type = base_type;
		}

		expect (TokenType.EOL);

		class_name = st.name;

		parse_declarations (st);

		Symbol result = st;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, st.source_reference);
			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_struct ((Struct) result);
			}
			result = ns;
		}
		return result;
	}

	void parse_struct_member (Struct st) throws ParseError {
		var sym = parse_declaration ();
		if (sym is Method) {
			st.add_method ((Method) sym);
		} else if (sym is Field) {
			st.add_field ((Field) sym);
		} else if (sym is Constant) {
			st.add_constant ((Constant) sym);
		} else if (sym is Property) {
			st.add_property ((Property) sym);
		} else {
			Report.error (sym.source_reference, "unexpected declaration in struct");
		}
	}

	Symbol parse_interface_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();

		expect (TokenType.INTERFACE);
		var flags = parse_type_declaration_modifiers ();
		var sym = parse_symbol_name ();
		var type_param_list = parse_type_parameter_list ();
		var base_types = new ArrayList<DataType> ();
		if (accept (TokenType.COLON)) {
			do {
				var type = parse_type (true, false);
				base_types.add (type);
			} while (accept (TokenType.COMMA));
		}

		var iface = new Interface (sym.name, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			iface.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			iface.access = SymbolAccessibility.PROTECTED;
		} else {
			iface.access = get_default_accessibility (sym.name);
		}
		if (ModifierFlags.EXTERN in flags) {
			iface.is_extern = true;
		}
		set_attributes (iface, attrs);
		foreach (TypeParameter type_param in type_param_list) {
			iface.add_type_parameter (type_param);
		}
		foreach (DataType base_type in base_types) {
			iface.add_prerequisite (base_type);
		}


		expect (TokenType.EOL);

		parse_declarations (iface);


		Symbol result = iface;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, iface.source_reference);
			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_interface ((Interface) result);
			}
			result = ns;
		}
		return result;
	}

	void parse_interface_member (Interface iface) throws ParseError {
		var sym = parse_declaration ();
		if (sym is Class) {
			iface.add_class ((Class) sym);
		} else if (sym is Struct) {
			iface.add_struct ((Struct) sym);
		} else if (sym is Enum) {
			iface.add_enum ((Enum) sym);
		} else if (sym is Delegate) {
			iface.add_delegate ((Delegate) sym);
		} else if (sym is Method) {
			iface.add_method ((Method) sym);
		} else if (sym is Vala.Signal) {
			iface.add_signal ((Vala.Signal) sym);
		} else if (sym is Field) {
			iface.add_field ((Field) sym);
		} else if (sym is Constant) {
			iface.add_constant ((Constant) sym);
		} else if (sym is Property) {
			iface.add_property ((Property) sym);
		} else {
			Report.error (sym.source_reference, "unexpected declaration in interface");
		}
	}

	Symbol parse_enum_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		expect (TokenType.ENUM);
		var flags = parse_type_declaration_modifiers ();

		var sym = parse_symbol_name ();
		var en = new Enum (sym.name, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			en.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			en.access = SymbolAccessibility.PROTECTED;
		} else {
			en.access = get_default_accessibility (sym.name);
		}
		if (ModifierFlags.EXTERN in flags) {
			en.is_extern = true;
		}
		set_attributes (en, attrs);

		expect (TokenType.EOL);
		expect (TokenType.INDENT);
		do {
			if (current () == TokenType.DEDENT && en.get_values ().size > 0) {
				// allow trailing comma
				break;
			}
			var value_attrs = parse_attributes (false);
			var value_begin = get_location ();
			string id = parse_identifier ();
			comment = scanner.pop_comment ();

			Expression value = null;
			if (accept (TokenType.ASSIGN)) {
				value = parse_expression ();
			}

			var ev = new EnumValue (id, value, get_src (value_begin), comment);
			ev.access = SymbolAccessibility.PUBLIC;
			set_attributes (ev, value_attrs);

			en.add_value (ev);
			if (expect_separator ()) {
				accept (TokenType.EOL);
			}
		} while (true);

		expect (TokenType.DEDENT);

		Symbol result = en;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, en.source_reference);
			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_enum ((Enum) result);
			}
			result = ns;
		}
		return result;
	}

	Symbol parse_errordomain_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		expect (TokenType.EXCEPTION);
		var flags = parse_type_declaration_modifiers ();

		var sym = parse_symbol_name ();
		var ed = new ErrorDomain (sym.name, get_src (begin), comment);
		if (ModifierFlags.PRIVATE in flags) {
			ed.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			ed.access = SymbolAccessibility.PROTECTED;
		} else {
			ed.access = get_default_accessibility (sym.name);
		}

		set_attributes (ed, attrs);

		expect (TokenType.EOL);
		expect (TokenType.INDENT);

		do {
			if (current () == TokenType.DEDENT && ed.get_codes ().size > 0) {
				// allow trailing comma
				break;
			}
			var code_attrs = parse_attributes (false);
			var code_begin = get_location ();
			string id = parse_identifier ();
			comment = scanner.pop_comment ();
			var ec = new ErrorCode (id, get_src (code_begin), comment);
			ec.access = SymbolAccessibility.PUBLIC;
			set_attributes (ec, code_attrs);
			if (accept (TokenType.ASSIGN)) {
				ec.value = parse_expression ();
			}
			ed.add_code (ec);
			accept (TokenType.EOL);
		} while (true);


		expect (TokenType.DEDENT);

		Symbol result = ed;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, ed.source_reference);

			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_error_domain ((ErrorDomain) result);
			}
			result = ns;
		}
		return result;
	}

	ModifierFlags parse_type_declaration_modifiers () {
		ModifierFlags flags = 0;
		while (true) {
			switch (current ()) {
			case TokenType.ABSTRACT:
				next ();
				flags |= ModifierFlags.ABSTRACT;
				break;

			case TokenType.EXTERN:
				next ();
				flags |= ModifierFlags.EXTERN;
				break;

			case TokenType.STATIC:
				next ();
				flags |= ModifierFlags.STATIC;
				break;

			case TokenType.PRIVATE:
				next ();
				flags |= ModifierFlags.PRIVATE;
				break;

			case TokenType.PUBLIC:
				next ();
				flags |= ModifierFlags.PUBLIC;
				break;

			case TokenType.PROTECTED:
				next ();
				flags |= ModifierFlags.PROTECTED;
				break;

			default:
				return flags;
			}
		}
	}

	ModifierFlags parse_member_declaration_modifiers () {
		ModifierFlags flags = 0;
		while (true) {
			switch (current ()) {
			case TokenType.ABSTRACT:
				next ();
				flags |= ModifierFlags.ABSTRACT;
				break;
			case TokenType.ASYNC:
				next ();
				flags |= ModifierFlags.ASYNC;
				break;
			case TokenType.CLASS:
				next ();
				flags |= ModifierFlags.CLASS;
				break;
			case TokenType.EXTERN:
				next ();
				flags |= ModifierFlags.EXTERN;
				break;
			case TokenType.INLINE:
				next ();
				flags |= ModifierFlags.INLINE;
				break;
			case TokenType.NEW:
				next ();
				flags |= ModifierFlags.NEW;
				break;
			case TokenType.OVERRIDE:
				next ();
				flags |= ModifierFlags.OVERRIDE;
				break;
			case TokenType.SEALED:
				next ();
				flags |= ModifierFlags.SEALED;
				break;
			case TokenType.STATIC:
				next ();
				flags |= ModifierFlags.STATIC;
				break;
			case TokenType.VIRTUAL:
				next ();
				flags |= ModifierFlags.VIRTUAL;
				break;
			case TokenType.PRIVATE:
				next ();
				flags |= ModifierFlags.PRIVATE;
				break;
			case TokenType.PUBLIC:
				next ();
				flags |= ModifierFlags.PUBLIC;
				break;
			case TokenType.PROTECTED:
				next ();
				flags |= ModifierFlags.PROTECTED;
				break;
			default:
				return flags;
			}
		}
	}

	Parameter parse_parameter () throws ParseError {
		var attrs = parse_attributes (true);
		var begin = get_location ();
		if (accept (TokenType.ELLIPSIS)) {
			// varargs
			return new Parameter.with_ellipsis (get_src (begin));
		}
		bool params_array = accept (TokenType.PARAMS);
		var direction = ParameterDirection.IN;
		if (accept (TokenType.OUT)) {
			direction = ParameterDirection.OUT;
		} else if (accept (TokenType.REF)) {
			direction = ParameterDirection.REF;
		}

		string id = parse_identifier ();

		expect (TokenType.COLON);

		DataType type;
		if (direction == ParameterDirection.IN) {
			 type = parse_type (false, false);
		} else if (direction == ParameterDirection.REF) {
			// ref parameters own the value by default
			type = parse_type (true, true);
		} else {
			// out parameters own the value by default
			type = parse_type (true, false);
		}

		var param = new Parameter (id, type, get_src (begin));
		set_attributes (param, attrs);
		param.direction = direction;
		param.params_array = params_array;
		if (accept (TokenType.ASSIGN)) {
			param.initializer = parse_expression ();
		}
		return param;
	}

	CreationMethod parse_creation_method_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		CreationMethod method;

		expect (TokenType.CONSTRUCT);
		var flags = parse_member_declaration_modifiers ();

		if (accept (TokenType.OPEN_PARENS)) {
			/* create default name using class name */
			method = new CreationMethod (class_name, null, get_src (begin), comment);
		} else {
			var sym = parse_symbol_name ();
			if (sym.inner == null) {

				if (sym.name != class_name) {
					method = new CreationMethod (class_name, sym.name, get_src (begin), comment);
				} else {
					method = new CreationMethod (sym.name, null, get_src (begin), comment);
				}
			} else {
				method = new CreationMethod (sym.inner.name, sym.name, get_src (begin), comment);
			}
			expect (TokenType.OPEN_PARENS);
		}

		if (current () != TokenType.CLOSE_PARENS) {
			do {
				var param = parse_parameter ();
				method.add_parameter (param);
			} while (accept (TokenType.COMMA));
		}
		expect (TokenType.CLOSE_PARENS);
		if (accept (TokenType.RAISES)) {
			do {
				method.add_error_type (parse_type (true, false));
			} while (accept (TokenType.COMMA));
		}

		if (ModifierFlags.PRIVATE in flags) {
			method.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			method.access = SymbolAccessibility.PROTECTED;
		} else {
			method.access = SymbolAccessibility.PUBLIC;
		}

		set_attributes (method, attrs);

		if (ModifierFlags.ASYNC in flags) {
			method.coroutine = true;
		}

		if (accept_block ()) {
			method.body = parse_block ();
			method.external = false;
		}

		return method;
	}

	Symbol parse_delegate_declaration (List<Attribute>? attrs) throws ParseError {
		var begin = get_location ();
		DataType type;

		expect (TokenType.DELEGATE);

		var flags = parse_member_declaration_modifiers ();

		var sym = parse_symbol_name ();

		var type_param_list = parse_type_parameter_list ();

		if (ModifierFlags.NEW in flags) {
			throw new ParseError.SYNTAX ("`new' modifier not allowed on delegates");
		}

		var params = new ArrayList<Parameter> ();

		expect (TokenType.OPEN_PARENS);
		if (current () != TokenType.CLOSE_PARENS) {
			do {
				var param = parse_parameter ();
				params.add (param);
			} while (accept (TokenType.COMMA));
		}
		expect (TokenType.CLOSE_PARENS);

		if (accept (TokenType.COLON)) {
			type = parse_type (true, false);
		} else {
			type = new VoidType ();
		}

		var d = new Delegate (sym.name, type, get_src (begin), comment);

		if (accept (TokenType.RAISES)) {
			do {
				d.add_error_type (parse_type (true, false));
			} while (accept (TokenType.COMMA));
		}

		expect_terminator ();


		if (ModifierFlags.PRIVATE in flags) {
			d.access = SymbolAccessibility.PRIVATE;
		} else if (ModifierFlags.PROTECTED in flags) {
			d.access = SymbolAccessibility.PROTECTED;
		} else {
			d.access = get_default_accessibility (sym.name);
		}

		if (ModifierFlags.STATIC in flags) {
			d.has_target = false;
		}
		if (ModifierFlags.EXTERN in flags) {
			d.is_extern = true;
		}

		set_attributes (d, attrs);

		foreach (TypeParameter type_param in type_param_list) {
			d.add_type_parameter (type_param);
		}

		foreach (Parameter formal_param in params) {
			d.add_parameter (formal_param);
		}



		Symbol result = d;
		while (sym.inner != null) {
			sym = sym.inner;
			var ns = new Namespace (sym.name, d.source_reference);

			if (result is Namespace) {
				ns.add_namespace ((Namespace) result);
			} else {
				ns.add_delegate ((Delegate) result);
			}
			result = ns;
		}
		return result;
	}

	List<TypeParameter> parse_type_parameter_list () throws ParseError {
		if (accept (TokenType.OF)) {
			var list = new ArrayList<TypeParameter> ();
			do {
				var begin = get_location ();
				string id = parse_identifier ();
				list.add (new TypeParameter (id, get_src (begin)));
			} while (accept (TokenType.COMMA));
			return list;
		} else {
			if (_empty_type_parameter_list == null) {
				_empty_type_parameter_list = new ArrayList<TypeParameter> ();
			}
			return _empty_type_parameter_list;
		}
	}

	void skip_type_argument_list () throws ParseError {
		if (accept (TokenType.OF)) {
			if (accept (TokenType.OPEN_PARENS)) {
				do {
					skip_type ();
				} while (accept (TokenType.COMMA));
				expect (TokenType.CLOSE_PARENS);
			} else {
				do {
					skip_type ();
				} while (accept (TokenType.COMMA));
			}
		}
	}


	// try to parse type argument list
	List<DataType>? parse_type_argument_list (bool maybe_expression) throws ParseError {
		var begin = get_location ();
		if (accept (TokenType.OF)) {
			var list = new ArrayList<DataType> ();
			var inParens = false;

			// Optional parens allow multi arg types in function signature: "dict of (int, string)"
			// See: https://bugzilla.gnome.org/show_bug.cgi?id=611191
			if (accept (TokenType.OPEN_PARENS)) {
				inParens = true;
			}

			do {
				switch (current ()) {
				case TokenType.VOID:
				case TokenType.DYNAMIC:
				case TokenType.UNOWNED:
				case TokenType.WEAK:
				case TokenType.IDENTIFIER:
					var type = parse_type (true, true);

					list.add (type);
					break;
				default:
					rollback (begin);
					return null;
				}
			} while (accept (TokenType.COMMA));

			if (inParens) {
				expect (TokenType.CLOSE_PARENS);
			}

			return list;
		}
		return null;
	}

	MemberAccess parse_member_name (Expression? base_expr = null) throws ParseError {
		var begin = get_location ();
		MemberAccess expr = null;
		do {
			string id = parse_identifier ();
			List<DataType> type_arg_list = parse_type_argument_list (false);
			expr = new MemberAccess (expr != null ? expr : base_expr, id, get_src (begin));
			if (type_arg_list != null) {
				foreach (DataType type_arg in type_arg_list) {
					expr.add_type_argument (type_arg);
				}
			}
		} while (accept (TokenType.DOT));
		return expr;
	}
}