X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=oberon.c;h=931d948c57bc15c0faf906e0a6f23b52f991a122;hb=c4d4a265b71124ad0e8588601cfc1d66aca84b96;hp=65803c0d7eaf5924fdc96b42858b0eb3834c016d;hpb=063ba732ee8778c34a3781270b18d52481dbf0cd;p=dsw-obn.git

diff --git a/oberon.c b/oberon.c
index 65803c0..931d948 100644
--- a/oberon.c
+++ b/oberon.c
@@ -48,6 +48,12 @@ enum {
 	OF,
 	LBRACE,
 	RBRACE,
+	RECORD,
+	POINTER,
+	TO,
+	UPARROW,
+	NIL,
+	IMPORT
 };
 
 // =======================================================================
@@ -103,16 +109,19 @@ oberon_new_type_boolean(int size)
 static oberon_scope_t *
 oberon_open_scope(oberon_context_t * ctx)
 {
-	oberon_scope_t * scope = malloc(sizeof *scope);
-	memset(scope, 0, sizeof *scope);
-
-	oberon_object_t * list = malloc(sizeof *list);
-	memset(list, 0, sizeof *list);
+	oberon_scope_t * scope = calloc(1, sizeof *scope);
+	oberon_object_t * list = calloc(1, sizeof *list);
 
 	scope -> ctx = ctx;
 	scope -> list = list;
 	scope -> up = ctx -> decl;
 
+	if(scope -> up)
+	{
+		scope -> parent = scope -> up -> parent;
+		scope -> local = scope -> up -> local;
+	}
+
 	ctx -> decl = scope;
 	return scope;
 }
@@ -125,7 +134,7 @@ oberon_close_scope(oberon_scope_t * scope)
 }
 
 static oberon_object_t *
-oberon_define_object(oberon_scope_t * scope, char * name, int class)
+oberon_define_object(oberon_scope_t * scope, char * name, int class, int export, int read_only)
 {
 	oberon_object_t * x = scope -> list;
 	while(x -> next && strcmp(x -> next -> name, name) != 0)
@@ -142,6 +151,11 @@ oberon_define_object(oberon_scope_t * scope, char * name, int class)
 	memset(newvar, 0, sizeof *newvar);
 	newvar -> name = name;
 	newvar -> class = class;
+	newvar -> export = export;
+	newvar -> read_only = read_only;
+	newvar -> local = scope -> local;
+	newvar -> parent = scope -> parent;
+	newvar -> module = scope -> ctx -> mod;
 
 	x -> next = newvar;
 
@@ -160,7 +174,7 @@ oberon_find_object_in_list(oberon_object_t * list, char * name)
 }
 
 static oberon_object_t *
-oberon_find_object(oberon_scope_t * scope, char * name)
+oberon_find_object(oberon_scope_t * scope, char * name, int check_it)
 {
 	oberon_object_t * result = NULL;
 
@@ -171,7 +185,7 @@ oberon_find_object(oberon_scope_t * scope, char * name)
 		s = s -> up;
 	}
 
-	if(result == NULL)
+	if(check_it && result == NULL)
 	{
 		oberon_error(scope -> ctx, "undefined ident %s", name);
 	}
@@ -180,60 +194,31 @@ oberon_find_object(oberon_scope_t * scope, char * name)
 }
 
 static oberon_object_t *
-oberon_define_type(oberon_scope_t * scope, char * name, oberon_type_t * type)
-{
-	oberon_object_t * id;
-	id = oberon_define_object(scope, name, OBERON_CLASS_TYPE);
-	id -> type = type;
-	oberon_generator_init_type(scope -> ctx, type);
-	return id;
-}
-
-static oberon_type_t *
-oberon_find_type(oberon_scope_t * scope, char * name)
+oberon_find_field(oberon_context_t * ctx, oberon_type_t * rec, char * name)
 {
-	oberon_object_t * x = oberon_find_object(scope, name);
-	if(x -> class != OBERON_CLASS_TYPE)
+	oberon_object_t * x = rec -> decl;
+	for(int i = 0; i < rec -> num_decl; i++)
 	{
-		oberon_error(scope -> ctx, "%s not a type", name);
+		if(strcmp(x -> name, name) == 0)
+		{
+			return x;
+		}
+		x = x -> next;
 	}
 
-	return x -> type;
-}
-
-static oberon_object_t *
-oberon_define_var(oberon_scope_t * scope, int class, char * name, oberon_type_t * type)
-{
-	oberon_object_t * var;
-	var = oberon_define_object(scope, name, class);
-	var -> type = type;
-	oberon_generator_init_var(scope -> ctx, var);
-	return var;
-}
-
-/*
-static oberon_object_t *
-oberon_find_var(oberon_scope_t * scope, char * name)
-{
-	oberon_object_t * x = oberon_find_object(scope, name);
-
-	if(x -> class != OBERON_CLASS_VAR)
-	{
-		oberon_error(scope -> ctx, "%s not a var", name);
-	}
+	oberon_error(ctx, "field not defined");
 
-	return x;
+	return NULL;
 }
-*/
 
 static oberon_object_t *
-oberon_define_proc(oberon_scope_t * scope, char * name, oberon_type_t * signature)
+oberon_define_type(oberon_scope_t * scope, char * name, oberon_type_t * type, int export)
 {
-	oberon_object_t * proc;
-	proc = oberon_define_object(scope, name, OBERON_CLASS_PROC);
-	proc -> type = signature;
-	oberon_generator_init_proc(scope -> ctx, proc);
-	return proc;
+	oberon_object_t * id;
+	id = oberon_define_object(scope, name, OBERON_CLASS_TYPE, export, 0);
+	id -> type = type;
+	oberon_generator_init_type(scope -> ctx, type);
+	return id;
 }
 
 // =======================================================================
@@ -243,8 +228,11 @@ oberon_define_proc(oberon_scope_t * scope, char * name, oberon_type_t * signatur
 static void
 oberon_get_char(oberon_context_t * ctx)
 {
-	ctx -> code_index += 1;
-	ctx -> c = ctx -> code[ctx -> code_index];
+	if(ctx -> code[ctx -> code_index])
+	{
+		ctx -> code_index += 1;
+		ctx -> c = ctx -> code[ctx -> code_index];
+	}
 }
 
 static void
@@ -338,6 +326,26 @@ oberon_read_ident(oberon_context_t * ctx)
 	{
 		ctx -> token = OF;
 	}
+	else if(strcmp(ident, "RECORD") == 0)
+	{
+		ctx -> token = RECORD;
+	}
+	else if(strcmp(ident, "POINTER") == 0)
+	{
+		ctx -> token = POINTER;
+	}
+	else if(strcmp(ident, "TO") == 0)
+	{
+		ctx -> token = TO;
+	}
+	else if(strcmp(ident, "NIL") == 0)
+	{
+		ctx -> token = NIL;
+	}
+	else if(strcmp(ident, "IMPORT") == 0)
+	{
+		ctx -> token = IMPORT;
+	}
 }
 
 static void
@@ -374,6 +382,43 @@ oberon_skip_space(oberon_context_t * ctx)
 	}
 }
 
+static void
+oberon_read_comment(oberon_context_t * ctx)
+{
+	int nesting = 1;
+	while(nesting >= 1)
+	{
+		if(ctx -> c == '(')
+		{
+			oberon_get_char(ctx);
+			if(ctx -> c == '*')
+			{
+				oberon_get_char(ctx);
+				nesting += 1;
+			}
+		}
+		else if(ctx -> c == '*')
+		{
+			oberon_get_char(ctx);
+			if(ctx -> c == ')')
+			{
+				oberon_get_char(ctx);
+				nesting -= 1;
+			}
+		}
+		else if(ctx -> c == 0)
+		{
+			oberon_error(ctx, "unterminated comment");
+		}
+		else
+		{
+			oberon_get_char(ctx);
+		}
+	}
+}
+
+static void oberon_read_token(oberon_context_t * ctx);
+
 static void
 oberon_read_symbol(oberon_context_t * ctx)
 {
@@ -403,6 +448,12 @@ oberon_read_symbol(oberon_context_t * ctx)
 		case '(':
 			ctx -> token = LPAREN;
 			oberon_get_char(ctx);
+			if(ctx -> c == '*')
+			{
+				oberon_get_char(ctx);
+				oberon_read_comment(ctx);
+				oberon_read_token(ctx);
+			}
 			break;
 		case ')':
 			ctx -> token = RPAREN;
@@ -445,6 +496,11 @@ oberon_read_symbol(oberon_context_t * ctx)
 		case '*':
 			ctx -> token = STAR;
 			oberon_get_char(ctx);
+			if(ctx -> c == ')')
+			{
+				oberon_get_char(ctx);
+				oberon_error(ctx, "unstarted comment");
+			}
 			break;
 		case '/':
 			ctx -> token = SLASH;
@@ -470,8 +526,12 @@ oberon_read_symbol(oberon_context_t * ctx)
 			ctx -> token = RBRACE;
 			oberon_get_char(ctx);
 			break;
+		case '^':
+			ctx -> token = UPARROW;
+			oberon_get_char(ctx);
+			break;
 		default:
-			oberon_error(ctx, "invalid char");
+			oberon_error(ctx, "invalid char %c", ctx -> c);
 			break;
 	}
 }
@@ -504,7 +564,8 @@ static void oberon_expect_token(oberon_context_t * ctx, int token);
 static oberon_expr_t * oberon_expr(oberon_context_t * ctx);
 static void oberon_assert_token(oberon_context_t * ctx, int token);
 static char * oberon_assert_ident(oberon_context_t * ctx);
-static oberon_type_t * oberon_type(oberon_context_t * ctx);
+static void oberon_type(oberon_context_t * ctx, oberon_type_t ** type);
+static oberon_item_t * oberon_const_expr(oberon_context_t * ctx);
 
 static oberon_expr_t *
 oberon_new_operator(int op, oberon_type_t * result, oberon_expr_t * left, oberon_expr_t * right)
@@ -515,6 +576,7 @@ oberon_new_operator(int op, oberon_type_t * result, oberon_expr_t * left, oberon
 
 	operator -> is_item = 0;
 	operator -> result = result;
+	operator -> read_only = 1;
 	operator -> op = op;
 	operator -> left = left;
 	operator -> right = right;
@@ -523,7 +585,7 @@ oberon_new_operator(int op, oberon_type_t * result, oberon_expr_t * left, oberon
 }
 
 static oberon_expr_t *
-oberon_new_item(int mode, oberon_type_t * result)
+oberon_new_item(int mode, oberon_type_t * result, int read_only)
 {
 	oberon_item_t * item;
         item = malloc(sizeof *item);
@@ -531,6 +593,7 @@ oberon_new_item(int mode, oberon_type_t * result)
 
 	item -> is_item = 1;
 	item -> result = result;
+	item -> read_only = read_only;
 	item -> mode = mode;
 
 	return (oberon_expr_t *)item;
@@ -571,7 +634,7 @@ oberon_make_unary_op(oberon_context_t * ctx, int token, oberon_expr_t * a)
 }
 
 static void
-oberon_expr_list(oberon_context_t * ctx, int * num_expr, oberon_expr_t ** first)
+oberon_expr_list(oberon_context_t * ctx, int * num_expr, oberon_expr_t ** first, int const_expr)
 {
 	oberon_expr_t * last;
 
@@ -581,7 +644,16 @@ oberon_expr_list(oberon_context_t * ctx, int * num_expr, oberon_expr_t ** first)
 	{
 		oberon_assert_token(ctx, COMMA);
 		oberon_expr_t * current;
-		current = oberon_expr(ctx);
+
+		if(const_expr)
+		{
+			current = (oberon_expr_t *) oberon_const_expr(ctx);
+		}
+		else
+		{
+			current = oberon_expr(ctx);
+		}
+
 		last -> next = current;
 		last = current;
 		*num_expr += 1;
@@ -591,9 +663,15 @@ oberon_expr_list(oberon_context_t * ctx, int * num_expr, oberon_expr_t ** first)
 static oberon_expr_t *
 oberon_autocast_to(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t * pref)
 {
-	if(expr -> result -> class != pref -> class)
+	if(pref -> class != expr -> result -> class)
 	{
-		oberon_error(ctx, "incompatible types");
+		if(pref -> class != OBERON_TYPE_PROCEDURE)
+		{
+			if(expr -> result -> class != OBERON_TYPE_POINTER)
+			{
+				oberon_error(ctx, "incompatible types");
+			}
+		}
 	}
 
 	if(pref -> class == OBERON_TYPE_INTEGER)
@@ -603,6 +681,24 @@ oberon_autocast_to(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t *
 			oberon_error(ctx, "incompatible size");
 		}
 	}
+	else if(pref -> class == OBERON_TYPE_RECORD)
+	{
+		if(expr -> result != pref)
+		{
+			printf("oberon_autocast_to: rec %p != %p\n", expr -> result, pref);
+			oberon_error(ctx, "incompatible record types");
+		}
+	}
+	else if(pref -> class == OBERON_TYPE_POINTER)
+	{
+		if(expr -> result -> base != pref -> base)
+		{
+			if(expr -> result -> base -> class != OBERON_TYPE_VOID)
+			{
+				oberon_error(ctx, "incompatible pointer types");
+			}
+		}
+	}
 
 	// TODO cast
 
@@ -622,7 +718,7 @@ oberon_autocast_call(oberon_context_t * ctx, oberon_expr_t * desig)
 		oberon_error(ctx, "expected mode CALL");
 	}
 
-	if(desig -> item.var -> class != OBERON_CLASS_PROC)
+	if(desig -> item.var -> type -> class != OBERON_TYPE_PROCEDURE)
 	{
 		oberon_error(ctx, "only procedures can be called");
 	}
@@ -644,166 +740,502 @@ oberon_autocast_call(oberon_context_t * ctx, oberon_expr_t * desig)
 	oberon_object_t * param = fn -> decl;
 	for(int i = 0; i < num_args; i++)
 	{
+		if(param -> class == OBERON_CLASS_VAR_PARAM)
+		{
+			if(arg -> read_only)
+			{
+				oberon_error(ctx, "assign to read-only var");
+			}
+
+			//if(arg -> is_item)
+			//{
+			//	switch(arg -> item.mode)
+			//	{
+			//		case MODE_VAR:
+			//		case MODE_INDEX:
+			//		case MODE_FIELD:
+			//		// Допустимо разыменование?
+			//		//case MODE_DEREF:
+			//			break;
+			//		default:
+			//			oberon_error(ctx, "var-parameter accept only variables");
+			//			break;
+			//	}
+			//}
+		}
 		oberon_autocast_to(ctx, arg, param -> type);
 		arg = arg -> next;
 		param = param -> next;
 	}
 }
 
-#define ISEXPR(x) \
-	(((x) == PLUS) \
-	|| ((x) == MINUS) \
-	|| ((x) == IDENT) \
-	|| ((x) == INTEGER) \
-	|| ((x) == LPAREN) \
-	|| ((x) == NOT) \
-	|| ((x) == TRUE) \
-	|| ((x) == FALSE))
-
 static oberon_expr_t *
-oberon_designator(oberon_context_t * ctx)
+oberon_make_call_func(oberon_context_t * ctx, oberon_object_t * proc, int num_args, oberon_expr_t * list_args)
 {
-	char * name;
-	oberon_object_t * var;
-	oberon_expr_t * expr;
-
-	name = oberon_assert_ident(ctx);
-	var = oberon_find_object(ctx -> decl, name);
-
-	switch(var -> class)
+	switch(proc -> class)
 	{
-		case OBERON_CLASS_CONST:
-			// TODO copy value
-			expr = (oberon_expr_t *) var -> value;
+		case OBERON_CLASS_PROC:
+			if(proc -> class != OBERON_CLASS_PROC)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
 			break;
 		case OBERON_CLASS_VAR:
 		case OBERON_CLASS_VAR_PARAM:
 		case OBERON_CLASS_PARAM:
-			expr = oberon_new_item(MODE_VAR, var -> type);
-			break;
-		case OBERON_CLASS_PROC:
-			expr = oberon_new_item(MODE_CALL, var -> type);
+			if(proc -> type -> class != OBERON_TYPE_PROCEDURE)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
 			break;
 		default:
-			oberon_error(ctx, "invalid designator");
+			oberon_error(ctx, "not a procedure");
 			break;
 	}
 
-	expr -> item.var = var;
-	return expr;
-}
+	oberon_expr_t * call;
 
-static oberon_expr_t *
-oberon_opt_proc_parens(oberon_context_t * ctx, oberon_expr_t * expr)
-{
-	assert(expr -> is_item == 1);
-	if(ctx -> token == LPAREN)
+	if(proc -> sysproc)
 	{
-		oberon_assert_token(ctx, LPAREN);
-
-		int num_args = 0;
-		oberon_expr_t * arguments = NULL;
-
-		if(ISEXPR(ctx -> token))
+		if(proc -> genfunc == NULL)
 		{
-			oberon_expr_list(ctx, &num_args, &arguments);
+			oberon_error(ctx, "not a function-procedure");
 		}
 
-		expr -> result = expr -> item.var -> type -> base;
-		expr -> item.mode = MODE_CALL;
-		expr -> item.num_args = num_args;
-		expr -> item.args = arguments;
-		oberon_assert_token(ctx, RPAREN);
+		call = proc -> genfunc(ctx, num_args, list_args);
+	}
+	else
+	{
+		if(proc -> type -> base -> class == OBERON_TYPE_VOID)
+		{
+			oberon_error(ctx, "attempt to call procedure in expression");
+		}
 
-		oberon_autocast_call(ctx, expr);
+		call = oberon_new_item(MODE_CALL, proc -> type -> base, 1);
+		call -> item.var = proc;
+		call -> item.num_args = num_args;
+		call -> item.args = list_args;
+		oberon_autocast_call(ctx, call);
 	}
 
-	return expr;
+	return call;
 }
 
-static oberon_expr_t *
-oberon_factor(oberon_context_t * ctx)
+static void
+oberon_make_call_proc(oberon_context_t * ctx, oberon_object_t * proc, int num_args, oberon_expr_t * list_args)
 {
-	oberon_expr_t * expr;
-
-	switch(ctx -> token)
+	switch(proc -> class)
 	{
-		case IDENT:
-			expr = oberon_designator(ctx);
-			expr = oberon_opt_proc_parens(ctx, expr);
-			break;
-		case INTEGER:
-			expr = oberon_new_item(MODE_INTEGER, ctx -> int_type);
-			expr -> item.integer = ctx -> integer;
-			oberon_assert_token(ctx, INTEGER);
-			break;
-		case TRUE:
-			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type);
-			expr -> item.boolean = 1;
-			oberon_assert_token(ctx, TRUE);
-			break;
-		case FALSE:
-			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type);
-			expr -> item.boolean = 0;
-			oberon_assert_token(ctx, FALSE);
-			break;
-		case LPAREN:
-			oberon_assert_token(ctx, LPAREN);
-			expr = oberon_expr(ctx);
-			oberon_assert_token(ctx, RPAREN);
+		case OBERON_CLASS_PROC:
+			if(proc -> class != OBERON_CLASS_PROC)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
 			break;
-		case NOT:
-			oberon_assert_token(ctx, NOT);
-			expr = oberon_factor(ctx);
-			expr = oberon_make_unary_op(ctx, NOT, expr);
+		case OBERON_CLASS_VAR:
+		case OBERON_CLASS_VAR_PARAM:
+		case OBERON_CLASS_PARAM:
+			if(proc -> type -> class != OBERON_TYPE_PROCEDURE)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
 			break;
 		default:
-			oberon_error(ctx, "invalid expression");
+			oberon_error(ctx, "not a procedure");
+			break;
 	}
 
-	return expr;
+	if(proc -> sysproc)
+	{
+		if(proc -> genproc == NULL)
+		{
+			oberon_error(ctx, "requres non-typed procedure");
+		}
+
+		proc -> genproc(ctx, num_args, list_args);
+	}
+	else
+	{
+		if(proc -> type -> base -> class != OBERON_TYPE_VOID)
+		{
+			oberon_error(ctx, "attempt to call function as non-typed procedure");
+		}
+
+		oberon_expr_t * call;
+		call = oberon_new_item(MODE_CALL, proc -> type -> base, 1);
+		call -> item.var = proc;
+		call -> item.num_args = num_args;
+		call -> item.args = list_args;
+		oberon_autocast_call(ctx, call);
+		oberon_generate_call_proc(ctx, call);
+	}
 }
 
-/*
- * oberon_autocast_binary_op автоматически переобразовывеат тип по след. правилам:
- *   1. Классы обоих типов должны быть одинаковы
- *   2. В качестве результата должен быть выбран больший тип.
- *   3. Если размер результат не должен быть меньше чем базовый int
- */
+#define ISEXPR(x) \
+	(((x) == PLUS) \
+	|| ((x) == MINUS) \
+	|| ((x) == IDENT) \
+	|| ((x) == INTEGER) \
+	|| ((x) == LPAREN) \
+	|| ((x) == NOT) \
+	|| ((x) == TRUE) \
+	|| ((x) == FALSE))
 
-static void
-oberon_autocast_binary_op(oberon_context_t * ctx, oberon_type_t * a, oberon_type_t * b, oberon_type_t ** result)
+static oberon_expr_t *
+oberno_make_dereferencing(oberon_context_t * ctx, oberon_expr_t * expr)
 {
-	if((a -> class) != (b -> class))
+	if(expr -> result -> class != OBERON_TYPE_POINTER)
 	{
-		oberon_error(ctx, "incompatible types");
+		oberon_error(ctx, "not a pointer");
 	}
 
-	if((a -> size) > (b -> size))
+	assert(expr -> is_item);
+
+	oberon_expr_t * selector;
+	selector = oberon_new_item(MODE_DEREF, expr -> result -> base, expr -> read_only);
+	selector -> item.parent = (oberon_item_t *) expr;
+
+	return selector;
+}
+
+static oberon_expr_t *
+oberon_make_array_selector(oberon_context_t * ctx, oberon_expr_t * desig, oberon_expr_t * index)
+{
+	if(desig -> result -> class == OBERON_TYPE_POINTER)
 	{
-		*result = a;
+		desig = oberno_make_dereferencing(ctx, desig);
 	}
-	else
+
+	assert(desig -> is_item);
+
+	if(desig -> result -> class != OBERON_TYPE_ARRAY)
 	{
-		*result = b;
+		oberon_error(ctx, "not array");
 	}
 
-	if(((*result) -> class) == OBERON_TYPE_INTEGER)
+	oberon_type_t * base;
+	base = desig -> result -> base;
+
+	if(index -> result -> class != OBERON_TYPE_INTEGER)
 	{
-		if(((*result) -> size) < (ctx -> int_type -> size))
+		oberon_error(ctx, "index must be integer");
+	}
+
+	// Статическая проверка границ массива
+	if(index -> is_item)
+	{
+		if(index -> item.mode == MODE_INTEGER)
 		{
-			*result = ctx -> int_type;
+			int arr_size = desig -> result -> size;
+			int index_int = index -> item.integer;
+			if(index_int < 0 || index_int > arr_size - 1)
+			{
+				oberon_error(ctx, "not in range (dimension size 0..%i)", arr_size - 1);
+			}
 		}
 	}
 
-	/* TODO: cast types */
-}
+	oberon_expr_t * selector;
+	selector = oberon_new_item(MODE_INDEX, base, desig -> read_only);
+	selector -> item.parent = (oberon_item_t *) desig;
+	selector -> item.num_args = 1;
+	selector -> item.args = index;
 
-#define ITMAKESBOOLEAN(x) \
-	(((x) >= EQUAL && (x) <= GEQ) || ((x) == OR) || ((x) == AND))
+	return selector;
+}
 
-#define ITUSEONLYINTEGER(x) \
-	((x) >= LESS && (x) <= GEQ)
+static oberon_expr_t *
+oberon_make_record_selector(oberon_context_t * ctx, oberon_expr_t * expr, char * name)
+{
+	if(expr -> result -> class == OBERON_TYPE_POINTER)
+	{
+		expr = oberno_make_dereferencing(ctx, expr);
+	}
+
+	assert(expr -> is_item == 1);
+
+	if(expr -> result -> class != OBERON_TYPE_RECORD)
+	{
+		oberon_error(ctx, "not record");
+	}
+
+	oberon_type_t * rec = expr -> result;
+
+	oberon_object_t * field;
+	field = oberon_find_field(ctx, rec, name);
+
+	if(field -> export == 0)
+	{
+		if(field -> module != ctx -> mod)
+		{
+			oberon_error(ctx, "field not exported");
+		}
+	}
+
+	int read_only = 0;
+	if(field -> read_only)
+	{
+		if(field -> module != ctx -> mod)
+		{
+			read_only = 1;
+		}
+	}
+
+	oberon_expr_t * selector;
+	selector = oberon_new_item(MODE_FIELD, field -> type, read_only);
+	selector -> item.var = field;
+	selector -> item.parent = (oberon_item_t *) expr;
+
+	return selector;
+}
+
+#define ISSELECTOR(x) \
+	(((x) == LBRACE) \
+	|| ((x) == DOT) \
+	|| ((x) == UPARROW))
+
+static oberon_object_t *
+oberon_qualident(oberon_context_t * ctx, char ** xname, int check)
+{
+	char * name;
+	oberon_object_t * x;
+
+	name = oberon_assert_ident(ctx);
+	x = oberon_find_object(ctx -> decl, name, check);
+
+	if(x != NULL)
+	{
+		if(x -> class == OBERON_CLASS_MODULE)
+		{
+			oberon_assert_token(ctx, DOT);
+			name = oberon_assert_ident(ctx);
+			/* Наличие объектов в левых модулях всегда проверяется */
+			x = oberon_find_object(x -> module -> decl, name, 1);
+
+			if(x -> export == 0)
+			{
+				oberon_error(ctx, "not exported");
+			}
+		}
+	}
+
+	if(xname)
+	{
+		*xname = name;
+	}
+
+	return x;
+}
+
+static oberon_expr_t *
+oberon_designator(oberon_context_t * ctx)
+{
+	char * name;
+	oberon_object_t * var;
+	oberon_expr_t * expr;
+
+	var = oberon_qualident(ctx, NULL, 1);
+
+	int read_only = 0;
+	if(var -> read_only)
+	{
+		if(var -> module != ctx -> mod)
+		{
+			read_only = 1;
+		}
+	}
+
+	switch(var -> class)
+	{
+		case OBERON_CLASS_CONST:
+			// TODO copy value
+			expr = (oberon_expr_t *) var -> value;
+			break;
+		case OBERON_CLASS_VAR:
+		case OBERON_CLASS_VAR_PARAM:
+		case OBERON_CLASS_PARAM:
+			expr = oberon_new_item(MODE_VAR, var -> type, read_only);
+			break;
+		case OBERON_CLASS_PROC:
+			expr = oberon_new_item(MODE_VAR, var -> type, 1);
+			break;
+		default:
+			oberon_error(ctx, "invalid designator");
+			break;
+	}
+	expr -> item.var = var;
+
+	while(ISSELECTOR(ctx -> token))
+	{
+		switch(ctx -> token)
+		{
+			case DOT:
+				oberon_assert_token(ctx, DOT);
+				name = oberon_assert_ident(ctx);
+				expr = oberon_make_record_selector(ctx, expr, name);
+				break;
+			case LBRACE:
+				oberon_assert_token(ctx, LBRACE);
+				int num_indexes = 0;
+				oberon_expr_t * indexes = NULL;
+				oberon_expr_list(ctx, &num_indexes, &indexes, 0);
+				oberon_assert_token(ctx, RBRACE);
+
+				for(int i = 0; i < num_indexes; i++)
+				{
+					expr = oberon_make_array_selector(ctx, expr, indexes);
+					indexes = indexes -> next;
+				}
+				break;
+			case UPARROW:
+				oberon_assert_token(ctx, UPARROW);
+				expr = oberno_make_dereferencing(ctx, expr);
+				break;
+			default:
+				oberon_error(ctx, "oberon_designator: wat");
+				break;
+		}
+	}
+	return expr;
+}
+
+static oberon_expr_t *
+oberon_opt_func_parens(oberon_context_t * ctx, oberon_expr_t * expr)
+{
+	assert(expr -> is_item == 1);
+
+	/* Если есть скобки - значит вызов. Если нет, то передаём указатель. */
+	if(ctx -> token == LPAREN)
+	{
+		oberon_assert_token(ctx, LPAREN);
+
+		int num_args = 0;
+		oberon_expr_t * arguments = NULL;
+
+		if(ISEXPR(ctx -> token))
+		{
+			oberon_expr_list(ctx, &num_args, &arguments, 0);
+		}
+
+		expr = oberon_make_call_func(ctx, expr -> item.var, num_args, arguments);
+
+		oberon_assert_token(ctx, RPAREN);
+	}
+
+	return expr;
+}
+
+static void
+oberon_opt_proc_parens(oberon_context_t * ctx, oberon_expr_t * expr)
+{
+	assert(expr -> is_item == 1);
+
+	int num_args = 0;
+	oberon_expr_t * arguments = NULL;
+
+	if(ctx -> token == LPAREN)
+	{
+		oberon_assert_token(ctx, LPAREN);
+
+		if(ISEXPR(ctx -> token))
+		{
+			oberon_expr_list(ctx, &num_args, &arguments, 0);
+		}
+
+		oberon_assert_token(ctx, RPAREN);
+	}
+
+	/* Вызов происходит даже без скобок */
+	oberon_make_call_proc(ctx, expr -> item.var, num_args, arguments);
+}
+
+static oberon_expr_t *
+oberon_factor(oberon_context_t * ctx)
+{
+	oberon_expr_t * expr;
+
+	switch(ctx -> token)
+	{
+		case IDENT:
+			expr = oberon_designator(ctx);
+			expr = oberon_opt_func_parens(ctx, expr);
+			break;
+		case INTEGER:
+			expr = oberon_new_item(MODE_INTEGER, ctx -> int_type, 1);
+			expr -> item.integer = ctx -> integer;
+			oberon_assert_token(ctx, INTEGER);
+			break;
+		case TRUE:
+			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type, 1);
+			expr -> item.boolean = 1;
+			oberon_assert_token(ctx, TRUE);
+			break;
+		case FALSE:
+			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type, 1);
+			expr -> item.boolean = 0;
+			oberon_assert_token(ctx, FALSE);
+			break;
+		case LPAREN:
+			oberon_assert_token(ctx, LPAREN);
+			expr = oberon_expr(ctx);
+			oberon_assert_token(ctx, RPAREN);
+			break;
+		case NOT:
+			oberon_assert_token(ctx, NOT);
+			expr = oberon_factor(ctx);
+			expr = oberon_make_unary_op(ctx, NOT, expr);
+			break;
+		case NIL:
+			oberon_assert_token(ctx, NIL);
+			expr = oberon_new_item(MODE_NIL, ctx -> void_ptr_type, 1);
+			break;
+		default:
+			oberon_error(ctx, "invalid expression");
+	}
+
+	return expr;
+}
+
+/*
+ * oberon_autocast_binary_op автоматически переобразовывеат тип по след. правилам:
+ *   1. Классы обоих типов должны быть одинаковы
+ *   2. В качестве результата должен быть выбран больший тип.
+ *   3. Если размер результат не должен быть меньше чем базовый int
+ */
+
+static void
+oberon_autocast_binary_op(oberon_context_t * ctx, oberon_type_t * a, oberon_type_t * b, oberon_type_t ** result)
+{
+	if((a -> class) != (b -> class))
+	{
+		oberon_error(ctx, "incompatible types");
+	}
+
+	if((a -> size) > (b -> size))
+	{
+		*result = a;
+	}
+	else
+	{
+		*result = b;
+	}
+
+	if(((*result) -> class) == OBERON_TYPE_INTEGER)
+	{
+		if(((*result) -> size) < (ctx -> int_type -> size))
+		{
+			*result = ctx -> int_type;
+		}
+	}
+
+	/* TODO: cast types */
+}
+
+#define ITMAKESBOOLEAN(x) \
+	(((x) >= EQUAL && (x) <= GEQ) || ((x) == OR) || ((x) == AND))
+
+#define ITUSEONLYINTEGER(x) \
+	((x) >= LESS && (x) <= GEQ)
 
 #define ITUSEONLYBOOLEAN(x) \
 	(((x) == OR) || ((x) == AND))
@@ -1007,7 +1439,9 @@ oberon_const_expr(oberon_context_t * ctx)
 //   PARSER
 // =======================================================================
 
+static void oberon_decl_seq(oberon_context_t * ctx);
 static void oberon_statement_seq(oberon_context_t * ctx);
+static void oberon_initialize_decl(oberon_context_t * ctx);
 
 static void
 oberon_expect_token(oberon_context_t * ctx, int token)
@@ -1034,127 +1468,122 @@ oberon_assert_ident(oberon_context_t * ctx)
 	return ident;
 }
 
-static oberon_type_t *
-oberon_make_array_type(oberon_context_t * ctx, int dim, oberon_item_t * size, oberon_type_t * base)
+static void
+oberon_def(oberon_context_t * ctx, int * export, int * read_only)
 {
-	assert(dim == 1);
-	oberon_type_t * newtype;
-
-	if(size -> mode != MODE_INTEGER)
+	switch(ctx -> token)
 	{
-		oberon_error(ctx, "requires integer constant");
+		case STAR:
+			oberon_assert_token(ctx, STAR);
+			*export = 1;
+			*read_only = 0;
+			break;
+		case MINUS:
+			oberon_assert_token(ctx, MINUS);
+			*export = 1;
+			*read_only = 1;
+			break;
+		default:
+			*export = 0;
+			*read_only = 0;
+			break;
 	}
+}
+
+static oberon_object_t *
+oberon_ident_def(oberon_context_t * ctx, int class)
+{
+	char * name;
+	int export;
+	int read_only;
+	oberon_object_t * x;
 
-	newtype = oberon_new_type_ptr(OBERON_TYPE_ARRAY);
-	newtype -> dim = dim;
-	newtype -> size = size -> integer;
-	newtype -> base = base;
-	oberon_generator_init_type(ctx, newtype);
+	name = oberon_assert_ident(ctx);
+	oberon_def(ctx, &export, &read_only);
 
-	return newtype;
+	x = oberon_define_object(ctx -> decl, name, class, export, read_only);
+	return x;
 }
 
-static oberon_type_t *
-oberon_type(oberon_context_t * ctx)
+static void
+oberon_ident_list(oberon_context_t * ctx, int class, int * num, oberon_object_t ** list)
 {
-	oberon_type_t * type;
-
-	if(ctx -> token == IDENT)
-	{
-		char * name = oberon_assert_ident(ctx);
-		type = oberon_find_type(ctx -> decl, name);
-	}
-	else if(ctx -> token == ARRAY)
-	{
-		oberon_assert_token(ctx, ARRAY);
-		oberon_item_t * size = oberon_const_expr(ctx);
-		oberon_assert_token(ctx, OF);
-		oberon_type_t * base = oberon_type(ctx);
-		type = oberon_make_array_type(ctx, 1, size, base);
-	}
-	else
+	*num = 1;
+	*list = oberon_ident_def(ctx, class);
+	while(ctx -> token == COMMA)
 	{
-		oberon_error(ctx, "invalid type declaration");
+		oberon_assert_token(ctx, COMMA);
+		oberon_ident_def(ctx, class);
+		*num += 1;
 	}
-
-	return type;
 }
 
 static void
 oberon_var_decl(oberon_context_t * ctx)
 {
-	char * name = oberon_assert_ident(ctx);
-	oberon_assert_token(ctx, COLON);
-	oberon_type_t * type = oberon_type(ctx);
-	oberon_define_var(ctx -> decl, OBERON_CLASS_VAR, name, type);
-}
+	int num;
+	oberon_object_t * list;
+	oberon_type_t * type;
+	type = oberon_new_type_ptr(OBERON_TYPE_VOID);
 
-static oberon_object_t *
-oberon_make_param(oberon_context_t * ctx, int token, char * name, oberon_type_t * type)
-{
-	oberon_object_t * param;
+	oberon_ident_list(ctx, OBERON_CLASS_VAR, &num, &list);
+	oberon_assert_token(ctx, COLON);
+	oberon_type(ctx, &type);
 
-	if(token == VAR)
-	{
-		param = oberon_define_var(ctx -> decl, OBERON_CLASS_VAR_PARAM, name, type);
-	}
-	else if(token == IDENT)
-	{
-		param = oberon_define_var(ctx -> decl, OBERON_CLASS_PARAM, name, type);
-	}
-	else
+	oberon_object_t * var = list;
+	for(int i = 0; i < num; i++)
 	{
-		oberon_error(ctx, "oberon_make_param: wat");
+		var -> type = type;
+		var = var -> next;
 	}
-
-	return param;
 }
 
 static oberon_object_t *
 oberon_fp_section(oberon_context_t * ctx, int * num_decl)
 {
-	int modifer_token = ctx -> token;
+	int class = OBERON_CLASS_PARAM;
 	if(ctx -> token == VAR)
 	{
 		oberon_read_token(ctx);
+		class = OBERON_CLASS_VAR_PARAM;
 	}
 
-	char * name;
-	name = oberon_assert_ident(ctx);
+	int num;
+	oberon_object_t * list;
+	oberon_ident_list(ctx, class, &num, &list);
 
 	oberon_assert_token(ctx, COLON);
 
 	oberon_type_t * type;
-	type = oberon_type(ctx);
+	type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+	oberon_type(ctx, &type);
 
-	oberon_object_t * first;
-	first = oberon_make_param(ctx, modifer_token, name, type);
+	oberon_object_t * param = list;
+	for(int i = 0; i < num; i++)
+	{
+		param -> type = type;
+		param = param -> next;
+	}
 
-	*num_decl += 1;
-	return first;
+	*num_decl += num;
+	return list;
 }
 
 #define ISFPSECTION \
 	((ctx -> token == VAR) || (ctx -> token == IDENT))
 
-static oberon_type_t *
-oberon_formal_pars(oberon_context_t * ctx)
+static void
+oberon_formal_pars(oberon_context_t * ctx, oberon_type_t * signature)
 {
-	oberon_type_t * tp;
-	tp = oberon_new_type_ptr(OBERON_TYPE_PROCEDURE);
-	tp -> num_decl = 0;
-	tp -> base = ctx -> void_type;
-	tp -> decl = NULL;
-
 	oberon_assert_token(ctx, LPAREN);
 
 	if(ISFPSECTION)
 	{
-		tp -> decl = oberon_fp_section(ctx, &tp -> num_decl);
+		signature -> decl = oberon_fp_section(ctx, &signature -> num_decl);
 		while(ctx -> token == SEMICOLON)
 		{
 			oberon_assert_token(ctx, SEMICOLON);
-			oberon_fp_section(ctx, &tp -> num_decl);
+			oberon_fp_section(ctx, &signature -> num_decl);
 		}
 	}
 
@@ -1163,17 +1592,68 @@ oberon_formal_pars(oberon_context_t * ctx)
 	if(ctx -> token == COLON)
 	{
 		oberon_assert_token(ctx, COLON);
-		tp -> base = oberon_type(ctx);
+
+		oberon_object_t * typeobj;
+		typeobj = oberon_qualident(ctx, NULL, 1);
+		if(typeobj -> class != OBERON_CLASS_TYPE)
+		{
+			oberon_error(ctx, "function result is not type");
+		}
+		signature -> base = typeobj -> type;
+	}
+}
+
+static void
+oberon_opt_formal_pars(oberon_context_t * ctx, oberon_type_t ** type)
+{
+	oberon_type_t * signature;
+	signature = *type;
+	signature -> class = OBERON_TYPE_PROCEDURE;
+	signature -> num_decl = 0;
+	signature -> base = ctx -> void_type;
+	signature -> decl = NULL;
+
+	if(ctx -> token == LPAREN)
+	{
+		oberon_formal_pars(ctx, signature);
+	}
+}
+
+static void
+oberon_compare_signatures(oberon_context_t * ctx, oberon_type_t * a, oberon_type_t * b)
+{
+	if(a -> num_decl != b -> num_decl)
+	{
+		oberon_error(ctx, "number parameters not matched");
 	}
 
-	oberon_generator_init_type(ctx, tp);
-	return tp;
+	int num_param = a -> num_decl;
+	oberon_object_t * param_a = a -> decl;
+	oberon_object_t * param_b = b -> decl;
+	for(int i = 0; i < num_param; i++)
+	{
+		if(strcmp(param_a -> name, param_b -> name) != 0)
+		{
+			oberon_error(ctx, "param %i name not matched", i + 1);
+		}
+
+		if(param_a -> type != param_b -> type)
+		{
+			oberon_error(ctx, "param %i type not matched", i + 1);
+		}
+
+		param_a = param_a -> next;
+		param_b = param_b -> next;
+	}
 }
 
 static void
 oberon_make_return(oberon_context_t * ctx, oberon_expr_t * expr)
 {
-	if(ctx -> result_type -> class == OBERON_TYPE_VOID)
+	oberon_object_t * proc = ctx -> decl -> parent;
+	oberon_type_t * result_type = proc -> type -> base;
+
+	if(result_type -> class == OBERON_TYPE_VOID)
 	{
 		if(expr != NULL)
 		{
@@ -1187,51 +1667,25 @@ oberon_make_return(oberon_context_t * ctx, oberon_expr_t * expr)
 			oberon_error(ctx, "procedure requires expression on result");
 		}
 
-		oberon_autocast_to(ctx, expr, ctx -> result_type);
+		oberon_autocast_to(ctx, expr, result_type);
 	}
 
-	ctx -> has_return = 1;
+	proc -> has_return = 1;
 
 	oberon_generate_return(ctx, expr);
 }
 
 static void
-oberon_proc_decl(oberon_context_t * ctx)
+oberon_proc_decl_body(oberon_context_t * ctx, oberon_object_t * proc)
 {
-	oberon_assert_token(ctx, PROCEDURE);
-
-	char * name;
-	name = oberon_assert_ident(ctx);
-
-	oberon_scope_t * this_proc_def_scope = ctx -> decl;
-	oberon_open_scope(ctx);
-
-	oberon_type_t * signature;
-	if(ctx -> token == LPAREN)
-	{
-		signature = oberon_formal_pars(ctx);
-	}
-	else
-	{
-		signature = oberon_new_type_ptr(OBERON_TYPE_PROCEDURE);
-		signature -> num_decl = 0;
-		signature -> base = ctx -> void_type;
-		signature -> decl = NULL;
-		oberon_generator_init_type(ctx, signature);
-	}
-
-	oberon_object_t * proc;
-	proc = oberon_define_proc(this_proc_def_scope, name, signature);
+	oberon_assert_token(ctx, SEMICOLON);
 
-	ctx -> result_type = signature -> base;
-	ctx -> has_return = 0;
+	ctx -> decl = proc -> scope;
 
-	oberon_assert_token(ctx, SEMICOLON);
+	oberon_decl_seq(ctx);
 
 	oberon_generate_begin_proc(ctx, proc);
 
-	// TODO declarations
-
 	if(ctx -> token == BEGIN)
 	{
 		oberon_assert_token(ctx, BEGIN);
@@ -1239,55 +1693,620 @@ oberon_proc_decl(oberon_context_t * ctx)
 	}
 
 	oberon_assert_token(ctx, END);
-	char * name2 = oberon_assert_ident(ctx);
-	if(strcmp(name2, name) != 0)
+	char * name = oberon_assert_ident(ctx);
+	if(strcmp(name, proc -> name) != 0)
 	{
 		oberon_error(ctx, "procedure name not matched");
 	}
 
-	if(signature -> base -> class == OBERON_TYPE_VOID)
+	if(proc -> type -> base -> class == OBERON_TYPE_VOID
+		&& proc -> has_return == 0)
 	{
 		oberon_make_return(ctx, NULL);
 	}
 
-	if(ctx -> has_return == 0)
+	if(proc -> has_return == 0)
 	{
 		oberon_error(ctx, "procedure requires return");
 	}
-	ctx -> result_type = NULL;
 
 	oberon_generate_end_proc(ctx);
 	oberon_close_scope(ctx -> decl);
 }
 
 static void
-oberon_const_decl(oberon_context_t * ctx)
+oberon_proc_decl(oberon_context_t * ctx)
 {
+	oberon_assert_token(ctx, PROCEDURE);
+
+	int forward = 0;
+	if(ctx -> token == UPARROW)
+	{
+		oberon_assert_token(ctx, UPARROW);
+		forward = 1;
+	}
+
 	char * name;
+	int export;
+	int read_only;
+	name = oberon_assert_ident(ctx);
+	oberon_def(ctx, &export, &read_only);
+
+	oberon_scope_t * proc_scope;
+	proc_scope = oberon_open_scope(ctx);
+	ctx -> decl -> local = 1;
+
+	oberon_type_t * signature;
+	signature = oberon_new_type_ptr(OBERON_TYPE_VOID);
+	oberon_opt_formal_pars(ctx, &signature);	
+
+	oberon_initialize_decl(ctx);
+	oberon_generator_init_type(ctx, signature);
+	oberon_close_scope(ctx -> decl);
+
+	oberon_object_t * proc;
+	proc = oberon_find_object(ctx -> decl, name, 0);
+	if(proc != NULL)
+	{
+		if(proc -> class != OBERON_CLASS_PROC)
+		{
+			oberon_error(ctx, "mult definition");
+		}
+
+		if(forward == 0)
+		{
+			if(proc -> linked)
+			{
+				oberon_error(ctx, "mult procedure definition");
+			}
+		}
+
+		if(proc -> export != export || proc -> read_only != read_only)
+		{
+			oberon_error(ctx, "export type not matched");
+		}
+
+		oberon_compare_signatures(ctx, proc -> type, signature);
+	}
+	else
+	{
+		proc = oberon_define_object(ctx -> decl, name, OBERON_CLASS_PROC, export, read_only);
+		proc -> type = signature;
+		proc -> scope = proc_scope;
+		oberon_generator_init_proc(ctx, proc);
+	}
+
+	proc -> scope -> parent = proc;
+
+	if(forward == 0)
+	{
+		proc -> linked = 1;
+		oberon_proc_decl_body(ctx, proc);
+	}
+}
+
+static void
+oberon_const_decl(oberon_context_t * ctx)
+{
 	oberon_item_t * value;
 	oberon_object_t * constant;
 
-	name = oberon_assert_ident(ctx);
+	constant = oberon_ident_def(ctx, OBERON_CLASS_CONST);
 	oberon_assert_token(ctx, EQUAL);
 	value = oberon_const_expr(ctx);
-
-	constant = oberon_define_object(ctx -> decl, name, OBERON_CLASS_CONST);
 	constant -> value = value;
 }
 
+static void
+oberon_make_array_type(oberon_context_t * ctx, oberon_expr_t * size, oberon_type_t * base, oberon_type_t ** type)
+{
+	if(size -> is_item == 0)
+	{
+		oberon_error(ctx, "requires constant");
+	}
+
+	if(size -> item.mode != MODE_INTEGER)
+	{
+		oberon_error(ctx, "requires integer constant");
+	}
+
+	oberon_type_t * arr;
+	arr = *type;
+	arr -> class = OBERON_TYPE_ARRAY;
+	arr -> size = size -> item.integer;
+	arr -> base = base;
+}
+
+static void
+oberon_field_list(oberon_context_t * ctx, oberon_type_t * rec)
+{
+	if(ctx -> token == IDENT)
+	{
+		int num;
+		oberon_object_t * list;
+		oberon_type_t * type;
+		type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+
+		oberon_ident_list(ctx, OBERON_CLASS_FIELD, &num, &list);
+		oberon_assert_token(ctx, COLON);
+		oberon_type(ctx, &type);
+
+		oberon_object_t * field = list;
+		for(int i = 0; i < num; i++)
+		{
+			field -> type = type;
+			field = field -> next;
+		}
+
+		rec -> num_decl += num;
+	}
+}
+
+static void
+oberon_qualident_type(oberon_context_t * ctx, oberon_type_t ** type)
+{
+	char * name;
+	oberon_object_t * to;
+
+	to = oberon_qualident(ctx, &name, 0);
+
+	//name = oberon_assert_ident(ctx);
+	//to = oberon_find_object(ctx -> decl, name, 0);
+
+	if(to != NULL)
+	{
+		if(to -> class != OBERON_CLASS_TYPE)
+		{
+			oberon_error(ctx, "not a type");
+		}
+	}
+	else
+	{
+		to = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE, 0, 0);
+		to -> type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+	}
+
+	*type = to -> type;
+}
+
+static void oberon_opt_formal_pars(oberon_context_t * ctx, oberon_type_t ** type);
+
+/*
+ * Правило граматики "type". Указатель type должен указывать на существующий объект!
+ */
+
+static void
+oberon_make_multiarray(oberon_context_t * ctx, oberon_expr_t * sizes, oberon_type_t * base, oberon_type_t ** type)
+{
+	if(sizes == NULL)
+	{
+		*type = base;
+		return;
+	}
+
+	oberon_type_t * dim;
+	dim = oberon_new_type_ptr(OBERON_TYPE_VOID);
+
+	oberon_make_multiarray(ctx, sizes -> next, base, &dim);
+
+	oberon_make_array_type(ctx, sizes, dim, type);
+}
+
+static void
+oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
+{
+	if(ctx -> token == IDENT)
+	{
+		oberon_qualident_type(ctx, type);
+	}
+	else if(ctx -> token == ARRAY)
+	{
+		oberon_assert_token(ctx, ARRAY);
+
+		int num_sizes = 0;
+		oberon_expr_t * sizes;
+		oberon_expr_list(ctx, &num_sizes, &sizes, 1);
+
+		oberon_assert_token(ctx, OF);
+
+		oberon_type_t * base;
+		base = oberon_new_type_ptr(OBERON_TYPE_VOID);
+		oberon_type(ctx, &base);
+
+		oberon_make_multiarray(ctx, sizes, base, type);
+	}
+	else if(ctx -> token == RECORD)
+	{
+		oberon_type_t * rec;
+		rec = *type;
+		rec -> class = OBERON_TYPE_RECORD;
+
+		oberon_scope_t * record_scope;
+		record_scope = oberon_open_scope(ctx);
+		// TODO parent object
+		//record_scope -> parent = NULL;
+		record_scope -> local = 1;
+
+		oberon_assert_token(ctx, RECORD);
+		oberon_field_list(ctx, rec);
+		while(ctx -> token == SEMICOLON)
+		{
+			oberon_assert_token(ctx, SEMICOLON);
+			oberon_field_list(ctx, rec);
+		}
+		oberon_assert_token(ctx, END);
+
+		rec -> decl = record_scope -> list -> next;
+		oberon_close_scope(record_scope);
+
+		*type = rec;
+	}
+	else if(ctx -> token == POINTER)
+	{
+		oberon_assert_token(ctx, POINTER);
+		oberon_assert_token(ctx, TO);
+
+		oberon_type_t * base;
+		base = oberon_new_type_ptr(OBERON_TYPE_VOID);
+		oberon_type(ctx, &base);
+
+		oberon_type_t * ptr;
+		ptr = *type;
+		ptr -> class = OBERON_TYPE_POINTER;
+		ptr -> base = base;
+	}
+	else if(ctx -> token == PROCEDURE)
+	{
+		oberon_open_scope(ctx);
+		oberon_assert_token(ctx, PROCEDURE);
+		oberon_opt_formal_pars(ctx, type);
+		oberon_close_scope(ctx -> decl);
+	}
+	else
+	{
+		oberon_error(ctx, "invalid type declaration");
+	}
+}
+
 static void
 oberon_type_decl(oberon_context_t * ctx)
 {
 	char * name;
 	oberon_object_t * newtype;
 	oberon_type_t * type;
+	int export;
+	int read_only;
 
 	name = oberon_assert_ident(ctx);
+	oberon_def(ctx, &export, &read_only);
+
+	newtype = oberon_find_object(ctx -> decl, name, 0);
+	if(newtype == NULL)
+	{
+		newtype = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE, export, read_only);
+		newtype -> type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+		assert(newtype -> type);
+	}
+	else
+	{
+		if(newtype -> class != OBERON_CLASS_TYPE)
+		{
+			oberon_error(ctx, "mult definition");
+		}
+
+		if(newtype -> linked)
+		{
+			oberon_error(ctx, "mult definition - already linked");
+		}
+
+		newtype -> export = export;
+		newtype -> read_only = read_only;
+	}
+
 	oberon_assert_token(ctx, EQUAL);
-	type = oberon_type(ctx);
 
-	newtype = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE);
+	type = newtype -> type;
+	oberon_type(ctx, &type);
+
+	if(type -> class == OBERON_TYPE_VOID)
+	{
+		oberon_error(ctx, "recursive alias declaration");
+	}
+
 	newtype -> type = type;
+	newtype -> linked = 1;
+}
+
+static void oberon_prevent_recursive_object(oberon_context_t * ctx, oberon_object_t * x);
+static void oberon_prevent_recursive_type(oberon_context_t * ctx, oberon_type_t * type);
+
+static void
+oberon_prevent_recursive_pointer(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class != OBERON_TYPE_POINTER
+		&& type -> class != OBERON_TYPE_ARRAY)
+	{
+		return;
+	}
+
+	if(type -> recursive)
+	{
+		oberon_error(ctx, "recursive pointer declaration");
+	}
+
+	if(type -> base -> class == OBERON_TYPE_POINTER)
+	{
+		oberon_error(ctx, "attempt to make pointer to pointer");
+	}
+
+	type -> recursive = 1;
+
+	oberon_prevent_recursive_pointer(ctx, type -> base);
+
+	type -> recursive = 0;
+}
+
+static void
+oberon_prevent_recursive_record(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class != OBERON_TYPE_RECORD)
+	{
+		return;
+	}
+
+	if(type -> recursive)
+	{
+		oberon_error(ctx, "recursive record declaration");
+	}
+
+	type -> recursive = 1;
+
+	int num_fields = type -> num_decl;
+	oberon_object_t * field = type -> decl;
+	for(int i = 0; i < num_fields; i++)
+	{
+		oberon_prevent_recursive_object(ctx, field);
+		field = field -> next;
+	}
+
+	type -> recursive = 0;	
+}
+static void
+oberon_prevent_recursive_procedure(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class != OBERON_TYPE_PROCEDURE)
+	{
+		return;
+	}
+
+	if(type -> recursive)
+	{
+		oberon_error(ctx, "recursive procedure declaration");
+	}
+
+	type -> recursive = 1;
+
+	int num_fields = type -> num_decl;
+	oberon_object_t * field = type -> decl;
+	for(int i = 0; i < num_fields; i++)
+	{
+		oberon_prevent_recursive_object(ctx, field);
+		field = field -> next;
+	}
+
+	type -> recursive = 0;	
+}
+
+static void
+oberon_prevent_recursive_array(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class != OBERON_TYPE_ARRAY)
+	{
+		return;
+	}
+
+	if(type -> recursive)
+	{
+		oberon_error(ctx, "recursive array declaration");
+	}
+
+	type -> recursive = 1;
+
+	oberon_prevent_recursive_type(ctx, type -> base);
+
+	type -> recursive = 0;
+}
+
+static void
+oberon_prevent_recursive_type(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class == OBERON_TYPE_POINTER)
+	{
+		oberon_prevent_recursive_pointer(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_RECORD)
+	{
+		oberon_prevent_recursive_record(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_ARRAY)
+	{
+		oberon_prevent_recursive_array(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_PROCEDURE)
+	{
+		oberon_prevent_recursive_procedure(ctx, type);
+	}
+}
+
+static void
+oberon_prevent_recursive_object(oberon_context_t * ctx, oberon_object_t * x)
+{
+	switch(x -> class)
+	{
+		case OBERON_CLASS_VAR:
+		case OBERON_CLASS_TYPE:
+		case OBERON_CLASS_PARAM:
+		case OBERON_CLASS_VAR_PARAM:
+		case OBERON_CLASS_FIELD:
+			oberon_prevent_recursive_type(ctx, x -> type);
+			break;
+		case OBERON_CLASS_CONST:
+		case OBERON_CLASS_PROC:
+		case OBERON_CLASS_MODULE:
+			break;
+		default:
+			oberon_error(ctx, "oberon_prevent_recursive_object: wat");
+			break;
+	}
+}
+
+static void
+oberon_prevent_recursive_decl(oberon_context_t * ctx)
+{
+	oberon_object_t * x = ctx -> decl -> list -> next;
+
+	while(x)
+	{
+		oberon_prevent_recursive_object(ctx, x);
+		x = x -> next;
+	}
+}
+
+static void oberon_initialize_object(oberon_context_t * ctx, oberon_object_t * x);
+static void oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type);
+
+static void
+oberon_initialize_record_fields(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class != OBERON_TYPE_RECORD)
+	{
+		return;
+	}
+
+	int num_fields = type -> num_decl;
+	oberon_object_t * field = type -> decl;
+	for(int i = 0; i < num_fields; i++)
+	{
+		if(field -> type -> class == OBERON_TYPE_POINTER)
+		{
+			oberon_initialize_type(ctx, field -> type);
+		}
+
+		oberon_initialize_object(ctx, field);
+		field = field -> next;
+	}
+
+	oberon_generator_init_record(ctx, type);
+}
+
+static void
+oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type)
+{
+	if(type -> class == OBERON_TYPE_VOID)
+	{
+		oberon_error(ctx, "undeclarated type");
+	}
+
+	if(type -> initialized)
+	{
+		return;
+	}
+
+	type -> initialized = 1;
+
+	if(type -> class == OBERON_TYPE_POINTER)
+	{
+		oberon_initialize_type(ctx, type -> base);
+		oberon_generator_init_type(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_ARRAY)
+	{
+		oberon_initialize_type(ctx, type -> base);		
+		oberon_generator_init_type(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_RECORD)
+	{
+		oberon_generator_init_type(ctx, type);
+		oberon_initialize_record_fields(ctx, type);
+	}
+	else if(type -> class == OBERON_TYPE_PROCEDURE)
+	{
+		int num_fields = type -> num_decl;
+		oberon_object_t * field = type -> decl;
+		for(int i = 0; i < num_fields; i++)
+		{
+			oberon_initialize_object(ctx, field);
+			field = field -> next;
+		}		
+
+		oberon_generator_init_type(ctx, type);
+	}
+	else
+	{
+		oberon_generator_init_type(ctx, type);
+	}
+}
+
+static void
+oberon_initialize_object(oberon_context_t * ctx, oberon_object_t * x)
+{
+	if(x -> initialized)
+	{
+		return;
+	}
+
+	x -> initialized = 1;
+
+	switch(x -> class)
+	{
+		case OBERON_CLASS_TYPE:
+			oberon_initialize_type(ctx, x -> type);
+			break;
+		case OBERON_CLASS_VAR:
+		case OBERON_CLASS_PARAM:
+		case OBERON_CLASS_VAR_PARAM:
+		case OBERON_CLASS_FIELD:
+			oberon_initialize_type(ctx, x -> type);
+			oberon_generator_init_var(ctx, x);
+			break;
+		case OBERON_CLASS_CONST:
+		case OBERON_CLASS_PROC:
+		case OBERON_CLASS_MODULE:
+			break;
+		default:
+			oberon_error(ctx, "oberon_initialize_object: wat");
+			break;
+	}
+}
+
+static void
+oberon_initialize_decl(oberon_context_t * ctx)
+{
+	oberon_object_t * x = ctx -> decl -> list;
+
+	while(x -> next)
+	{
+		oberon_initialize_object(ctx, x -> next);
+		x = x -> next;
+	}	
+}
+
+static void
+oberon_prevent_undeclarated_procedures(oberon_context_t * ctx)
+{
+	oberon_object_t * x = ctx -> decl -> list;
+
+	while(x -> next)
+	{
+		if(x -> next -> class == OBERON_CLASS_PROC)
+		{
+			if(x -> next -> linked == 0)
+			{
+				oberon_error(ctx, "unresolved forward declaration");
+			}
+		}
+		x = x -> next;
+	}	
 }
 
 static void
@@ -1323,27 +2342,30 @@ oberon_decl_seq(oberon_context_t * ctx)
 		}
 	}
 
+	oberon_prevent_recursive_decl(ctx);
+	oberon_initialize_decl(ctx);
+
 	while(ctx -> token == PROCEDURE)
 	{
 		oberon_proc_decl(ctx);
 		oberon_assert_token(ctx, SEMICOLON);
 	}
+
+	oberon_prevent_undeclarated_procedures(ctx);
 }
 
 static void
 oberon_assign(oberon_context_t * ctx, oberon_expr_t * src, oberon_expr_t * dst)
 {
+	if(dst -> read_only)
+	{
+		oberon_error(ctx, "read-only destination");
+	}
+
 	oberon_autocast_to(ctx, src, dst -> result);
 	oberon_generate_assign(ctx, src, dst);
 }
 
-static void
-oberon_make_call(oberon_context_t * ctx, oberon_expr_t * desig)
-{
-	oberon_autocast_call(ctx, desig);
-	oberon_generate_call_proc(ctx, desig);
-}
-
 static void
 oberon_statement(oberon_context_t * ctx)
 {
@@ -1361,8 +2383,7 @@ oberon_statement(oberon_context_t * ctx)
 		}
 		else
 		{
-			item1 = oberon_opt_proc_parens(ctx, item1);
-			oberon_make_call(ctx, item1);
+			oberon_opt_proc_parens(ctx, item1);
 		}
 	}
 	else if(ctx -> token == RETURN)
@@ -1392,10 +2413,74 @@ oberon_statement_seq(oberon_context_t * ctx)
 	}
 }
 
+static void
+oberon_import_module(oberon_context_t * ctx, char * alias, char * name)
+{
+	oberon_module_t * m = ctx -> module_list;
+	while(m && strcmp(m -> name, name) != 0)
+	{
+		m = m -> next;
+	}
+
+	if(m == NULL)
+	{
+		const char * code;
+		code = ctx -> import_module(name);
+		if(code == NULL)
+		{
+			oberon_error(ctx, "no such module");
+		}
+
+		m = oberon_compile_module(ctx, code);
+		assert(m);
+	}
+
+	if(m -> ready == 0)
+	{
+		oberon_error(ctx, "cyclic module import");
+	}
+
+	oberon_object_t * ident;
+	ident = oberon_define_object(ctx -> decl, alias, OBERON_CLASS_MODULE, 0, 0);
+	ident -> module = m;
+}
+
+static void
+oberon_import_decl(oberon_context_t * ctx)
+{
+	char * alias;
+	char * name;
+
+	alias = name = oberon_assert_ident(ctx);
+	if(ctx -> token == ASSIGN)
+	{
+		oberon_assert_token(ctx, ASSIGN);
+		name = oberon_assert_ident(ctx);
+	}
+
+	oberon_import_module(ctx, alias, name);
+}
+
+static void
+oberon_import_list(oberon_context_t * ctx)
+{
+	oberon_assert_token(ctx, IMPORT);
+
+	oberon_import_decl(ctx);
+	while(ctx -> token == COMMA)
+	{
+		oberon_assert_token(ctx, COMMA);
+		oberon_import_decl(ctx);
+	}
+
+	oberon_assert_token(ctx, SEMICOLON);
+}
+
 static void
 oberon_parse_module(oberon_context_t * ctx)
 {
-	char *name1, *name2;
+	char * name1;
+	char * name2;
 	oberon_read_token(ctx);
 
 	oberon_assert_token(ctx, MODULE);
@@ -1403,15 +2488,20 @@ oberon_parse_module(oberon_context_t * ctx)
 	oberon_assert_token(ctx, SEMICOLON);
 	ctx -> mod -> name = name1;
 
+	if(ctx -> token == IMPORT)
+	{
+		oberon_import_list(ctx);
+	}
+
 	oberon_decl_seq(ctx);
 
+	oberon_generate_begin_module(ctx);
 	if(ctx -> token == BEGIN)
 	{
 		oberon_assert_token(ctx, BEGIN);
-		oberon_generate_begin_module(ctx);
 		oberon_statement_seq(ctx);
-		oberon_generate_end_module(ctx);
 	}
+	oberon_generate_end_module(ctx);
 
 	oberon_assert_token(ctx, END);
 	name2 = oberon_assert_ident(ctx);
@@ -1433,26 +2523,137 @@ register_default_types(oberon_context_t * ctx)
 	ctx -> void_type = oberon_new_type_ptr(OBERON_TYPE_VOID);
 	oberon_generator_init_type(ctx, ctx -> void_type);
 
+	ctx -> void_ptr_type = oberon_new_type_ptr(OBERON_TYPE_POINTER);
+	ctx -> void_ptr_type -> base = ctx -> void_type;
+	oberon_generator_init_type(ctx, ctx -> void_ptr_type);
+
 	ctx -> int_type = oberon_new_type_integer(sizeof(int));
-	oberon_define_type(ctx -> world_scope, "INTEGER", ctx -> int_type);
+	oberon_define_type(ctx -> world_scope, "INTEGER", ctx -> int_type, 1);
 
 	ctx -> bool_type = oberon_new_type_boolean(sizeof(int));
-	oberon_define_type(ctx -> world_scope, "BOOLEAN", ctx -> bool_type);
+	oberon_define_type(ctx -> world_scope, "BOOLEAN", ctx -> bool_type, 1);
+}
+
+static void
+oberon_new_intrinsic(oberon_context_t * ctx, char * name, GenerateFuncCallback f, GenerateProcCallback p)
+{
+	oberon_object_t * proc;
+	proc = oberon_define_object(ctx -> decl, name, OBERON_CLASS_PROC, 1, 0);
+	proc -> sysproc = 1;
+	proc -> genfunc = f;
+	proc -> genproc = p;
+	proc -> type = oberon_new_type_ptr(OBERON_TYPE_PROCEDURE);
+}
+
+static oberon_expr_t *
+oberon_make_abs_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
+{
+	if(num_args < 1)
+	{
+		oberon_error(ctx, "too few arguments");
+	}
+
+	if(num_args > 1)
+	{
+		oberon_error(ctx, "too mach arguments");
+	}
+
+	oberon_expr_t * arg;
+	arg = list_args;
+
+	oberon_type_t * result_type;
+	result_type = arg -> result;
+	
+	if(result_type -> class != OBERON_TYPE_INTEGER)
+	{
+		oberon_error(ctx, "ABS accepts only integers");
+	}
+
+
+	oberon_expr_t * expr;
+	expr = oberon_new_operator(OP_ABS, result_type, arg, NULL);
+	return expr;
+}
+
+static void
+oberon_make_new_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
+{
+	if(num_args < 1)
+	{
+		oberon_error(ctx, "too few arguments");
+	}
+
+	if(num_args > 1)
+	{
+		oberon_error(ctx, "too mach arguments");
+	}
+
+	oberon_expr_t * dst;
+	dst = list_args;
+
+	oberon_type_t * type;
+	type = dst -> result;
+
+	if(type -> class != OBERON_TYPE_POINTER)
+	{
+		oberon_error(ctx, "not a pointer");
+	}
+
+	type = type -> base;
+
+	oberon_expr_t * src;
+	if(type -> class == OBERON_TYPE_ARRAY)
+	{
+		int dim = 1;
+
+		oberon_expr_t * sizes = NULL;
+		oberon_expr_t * last_size = NULL;
+
+		sizes = last_size = oberon_new_item(MODE_INTEGER, ctx -> int_type, 1);
+		sizes -> item.integer = type -> size;
+
+		oberon_type_t * base = type -> base;
+		while(base -> class == OBERON_TYPE_ARRAY)
+		{
+			oberon_expr_t * size;
+			size = last_size = oberon_new_item(MODE_INTEGER, ctx -> int_type, 1);
+			size -> item.integer = base -> size;
+
+			last_size -> next = size;
+			last_size = size;
+			base = base -> base;
+			dim += 1;
+		}
+
+		src = oberon_new_item(MODE_NEWARR, dst -> result, 0);
+		src -> item.num_args = dim;
+		src -> item.args = sizes;
+		src -> item.type = base;
+	}
+	else
+	{
+		oberon_error(ctx, "oberon_make_new_call: wat");
+	}
+
+	oberon_assign(ctx, src, dst);
 }
 
 oberon_context_t *
-oberon_create_context()
+oberon_create_context(ModuleImportCallback import_module)
 {
-	oberon_context_t * ctx = malloc(sizeof *ctx);
-	memset(ctx, 0, sizeof *ctx);
+	oberon_context_t * ctx = calloc(1, sizeof *ctx);
 
 	oberon_scope_t * world_scope;
 	world_scope = oberon_open_scope(ctx);
 	ctx -> world_scope = world_scope;
 
+	ctx -> import_module = import_module;
+
 	oberon_generator_init_context(ctx);
 
-	register_default_types(ctx);	
+	register_default_types(ctx);
+	oberon_new_intrinsic(ctx, "ABS", oberon_make_abs_call, NULL);
+	oberon_new_intrinsic(ctx, "NEW", NULL, oberon_make_new_call);
 
 	return ctx;
 }
@@ -1465,21 +2666,41 @@ oberon_destroy_context(oberon_context_t * ctx)
 }
 
 oberon_module_t *
-oberon_compile_module(oberon_context_t * ctx, const char * code)
+oberon_compile_module(oberon_context_t * ctx, const char * newcode)
 {
-	oberon_module_t * mod = malloc(sizeof *mod);
-	memset(mod, 0, sizeof *mod);
-	ctx -> mod = mod;
+	const char * code = ctx -> code;
+	int code_index = ctx -> code_index;
+	char c = ctx -> c;
+	int token = ctx -> token;
+	char * string = ctx -> string;
+	int integer = ctx -> integer;
+	oberon_scope_t * decl = ctx -> decl;
+	oberon_module_t * mod = ctx -> mod;
 
 	oberon_scope_t * module_scope;
 	module_scope = oberon_open_scope(ctx);
-	mod -> decl = module_scope;
 
-	oberon_init_scaner(ctx, code);
+	oberon_module_t * module;
+	module = calloc(1, sizeof *module);
+	module -> decl = module_scope;
+	module -> next = ctx -> module_list;
+
+	ctx -> mod = module;
+	ctx -> module_list = module;
+
+	oberon_init_scaner(ctx, newcode);
 	oberon_parse_module(ctx);
 
-	oberon_generate_code(ctx);
+	module -> ready = 1;
+
+	ctx -> code = code;
+	ctx -> code_index = code_index;
+	ctx -> c = c;
+	ctx -> token = token;
+	ctx -> string = string;
+	ctx -> integer = integer;
+	ctx -> decl = decl;
+	ctx -> mod = mod;
 
-	ctx -> mod = NULL;
-	return mod;
+	return module;
 }