X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=oberon.c;h=16043c2f7aa0e4bdcd658130a5765b126b385b11;hb=e763da864f7330c2b53029782c6b0d85543eb4d2;hp=b7ffd0ea73ab2b9cd366a04d96a2b1e16a80a94d;hpb=060a955ff58efde6cb51ab18eaed8f479e2550f3;p=dsw-obn.git

diff --git a/oberon.c b/oberon.c
index b7ffd0e..16043c2 100644
--- a/oberon.c
+++ b/oberon.c
@@ -4,6 +4,7 @@
 #include <ctype.h>
 #include <string.h>
 #include <assert.h>
+#include <stdbool.h>
 
 #include "oberon.h"
 #include "generator.h"
@@ -52,7 +53,9 @@ enum {
 	POINTER,
 	TO,
 	UPARROW,
-	NIL
+	NIL,
+	IMPORT,
+	REAL
 };
 
 // =======================================================================
@@ -101,6 +104,15 @@ oberon_new_type_boolean(int size)
 	return x;
 }
 
+static oberon_type_t *
+oberon_new_type_real(int size)
+{
+	oberon_type_t * x;
+	x = oberon_new_type_ptr(OBERON_TYPE_REAL);
+	x -> size = size;
+	return x;
+}
+
 // =======================================================================
 //   TABLE
 // ======================================================================= 
@@ -108,16 +120,19 @@ 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;
 }
@@ -130,7 +145,7 @@ 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)
@@ -147,36 +162,17 @@ 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;
 
 	return newvar;
 }
 
-static void
-oberon_define_field(oberon_context_t * ctx, oberon_type_t * rec, char *  name, oberon_type_t * type)
-{
-	oberon_object_t * x = rec -> decl;
-	while(x -> next && strcmp(x -> next -> name, name) != 0)
-	{
-		x = x -> next;
-	}
-
-	if(x -> next)
-	{
-		oberon_error(ctx, "multiple definition");
-	}
-
-	oberon_object_t * field = malloc(sizeof *field);
-	memset(field, 0, sizeof *field);
-	field -> name = name;
-	field -> class = OBERON_CLASS_FIELD;
-	field -> type = type;
-
-	rec -> num_decl += 1;
-	x -> next = field;
-}
-
 static oberon_object_t *
 oberon_find_object_in_list(oberon_object_t * list, char * name)
 {
@@ -227,62 +223,15 @@ oberon_find_field(oberon_context_t * ctx, oberon_type_t * rec, char * name)
 }
 
 static oberon_object_t *
-oberon_define_type(oberon_scope_t * scope, char * name, oberon_type_t * type)
+oberon_define_type(oberon_scope_t * scope, char * name, oberon_type_t * type, int export)
 {
 	oberon_object_t * id;
-	id = oberon_define_object(scope, name, OBERON_CLASS_TYPE);
+	id = oberon_define_object(scope, name, OBERON_CLASS_TYPE, export, 0);
 	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_object_t * x = oberon_find_object(scope, name);
-	if(x -> class != OBERON_CLASS_TYPE)
-	{
-		oberon_error(scope -> ctx, "%s not a type", name);
-	}
-
-	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;
-	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);
-	}
-
-	return x;
-}
-*/
-
-static oberon_object_t *
-oberon_define_proc(oberon_scope_t * scope, char * name, oberon_type_t * signature)
-{
-	oberon_object_t * proc;
-	proc = oberon_define_object(scope, name, OBERON_CLASS_PROC);
-	proc -> type = signature;
-	return proc;
-}
-
 // =======================================================================
 //   SCANER
 // ======================================================================= 
@@ -290,8 +239,11 @@ 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
@@ -401,31 +353,126 @@ oberon_read_ident(oberon_context_t * ctx)
 	{
 		ctx -> token = NIL;
 	}
+	else if(strcmp(ident, "IMPORT") == 0)
+	{
+		ctx -> token = IMPORT;
+	}
 }
 
 static void
-oberon_read_integer(oberon_context_t * ctx)
-{
-	int len = 0;
-	int i = ctx -> code_index;
+oberon_read_number(oberon_context_t * ctx)
+{
+	long integer;
+	double real;
+	char * ident;
+	int start_i;
+	int exp_i;
+	int end_i;
+
+	/*
+	 * mode = 0 == DEC
+	 * mode = 1 == HEX
+	 * mode = 2 == REAL
+	 * mode = 3 == LONGREAL
+	 */
+	int mode = 0;
+	start_i = ctx -> code_index;
+
+	while(isdigit(ctx -> c))
+	{
+		oberon_get_char(ctx);
+	}
 
-	int c = ctx -> code[i];
-	while(isdigit(c))
+	end_i = ctx -> code_index;
+
+	if(isxdigit(ctx -> c))
 	{
-		i += 1;
-		len += 1;
-		c = ctx -> code[i];
+		mode = 1;
+		while(isxdigit(ctx -> c))
+		{
+			oberon_get_char(ctx);
+		}
+
+		end_i = ctx -> code_index;
+
+		if(ctx -> c != 'H')
+		{
+			oberon_error(ctx, "invalid hex number");
+		}
+		oberon_get_char(ctx);
 	}
+	else if(ctx -> c == '.')
+	{
+		mode = 2;
+		oberon_get_char(ctx);
 
-	char * ident = malloc(len + 2);
-	memcpy(ident, &ctx->code[ctx->code_index], len);
-	ident[len + 1] = 0;
+		while(isdigit(ctx -> c))
+		{
+			oberon_get_char(ctx);
+		}
+
+		if(ctx -> c == 'E' || ctx -> c == 'D')
+		{
+			exp_i = ctx -> code_index;
+
+			if(ctx -> c == 'D')
+			{
+				mode = 3;
+			}
+
+			oberon_get_char(ctx);
+
+			if(ctx -> c == '+' || ctx -> c == '-')
+			{
+				oberon_get_char(ctx);
+			}
+
+			while(isdigit(ctx -> c))
+			{
+				oberon_get_char(ctx);
+			}
+
+		}
+
+		end_i = ctx -> code_index;
+	}
+
+	int len = end_i - start_i;
+	ident = malloc(len + 1);
+	memcpy(ident, &ctx -> code[start_i], len);
+	ident[len] = 0;
+
+	if(mode == 3)
+	{
+		int i = exp_i - start_i;
+		ident[i] = 'E';
+	}
+
+	switch(mode)
+	{
+		case 0:
+			integer = atol(ident);
+			real = integer;
+			ctx -> token = INTEGER;
+			break;
+		case 1:
+			sscanf(ident, "%lx", &integer);
+			real = integer;
+			ctx -> token = INTEGER;
+			break;
+		case 2:
+		case 3:
+			sscanf(ident, "%lf", &real);
+			ctx -> token = REAL;
+			break;
+		default:
+			oberon_error(ctx, "oberon_read_number: wat");
+			break;
+	}
 
-	ctx -> code_index = i;
-	ctx -> c = ctx -> code[i];
 	ctx -> string = ident;
-	ctx -> integer = atoi(ident);
-	ctx -> token = INTEGER;
+	ctx -> integer = integer;
+	ctx -> real = real;
 }
 
 static void
@@ -437,6 +484,43 @@ 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)
 {
@@ -466,6 +550,12 @@ 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;
@@ -508,6 +598,11 @@ 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;
@@ -538,7 +633,7 @@ oberon_read_symbol(oberon_context_t * ctx)
 			oberon_get_char(ctx);
 			break;
 		default:
-			oberon_error(ctx, "invalid char");
+			oberon_error(ctx, "invalid char %c", ctx -> c);
 			break;
 	}
 }
@@ -555,7 +650,7 @@ oberon_read_token(oberon_context_t * ctx)
 	}
 	else if(isdigit(c))
 	{
-		oberon_read_integer(ctx);
+		oberon_read_number(ctx);
 	}
 	else
 	{
@@ -583,6 +678,7 @@ 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;
@@ -591,7 +687,7 @@ 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);
@@ -599,6 +695,7 @@ 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;
@@ -670,7 +767,13 @@ oberon_autocast_to(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t *
 {
 	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)
@@ -717,7 +820,7 @@ 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");
 	}
@@ -739,12 +842,137 @@ 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;
 	}
 }
 
+static oberon_expr_t *
+oberon_make_call_func(oberon_context_t * ctx, oberon_object_t * proc, int num_args, oberon_expr_t * list_args)
+{
+	switch(proc -> class)
+	{
+		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:
+			if(proc -> type -> class != OBERON_TYPE_PROCEDURE)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
+			break;
+		default:
+			oberon_error(ctx, "not a procedure");
+			break;
+	}
+
+	oberon_expr_t * call;
+
+	if(proc -> sysproc)
+	{
+		if(proc -> genfunc == NULL)
+		{
+			oberon_error(ctx, "not a function-procedure");
+		}
+
+		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");
+		}
+
+		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 call;
+}
+
+static void
+oberon_make_call_proc(oberon_context_t * ctx, oberon_object_t * proc, int num_args, oberon_expr_t * list_args)
+{
+	switch(proc -> class)
+	{
+		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:
+			if(proc -> type -> class != OBERON_TYPE_PROCEDURE)
+			{
+				oberon_error(ctx, "not a procedure");
+			}
+			break;
+		default:
+			oberon_error(ctx, "not a procedure");
+			break;
+	}
+
+	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);
+	}
+}
+
 #define ISEXPR(x) \
 	(((x) == PLUS) \
 	|| ((x) == MINUS) \
@@ -766,7 +994,7 @@ oberno_make_dereferencing(oberon_context_t * ctx, oberon_expr_t * expr)
 	assert(expr -> is_item);
 
 	oberon_expr_t * selector;
-	selector = oberon_new_item(MODE_DEREF, expr -> result -> base);
+	selector = oberon_new_item(MODE_DEREF, expr -> result -> base, expr -> read_only);
 	selector -> item.parent = (oberon_item_t *) expr;
 
 	return selector;
@@ -790,29 +1018,30 @@ oberon_make_array_selector(oberon_context_t * ctx, oberon_expr_t * desig, oberon
 	oberon_type_t * base;
 	base = desig -> result -> base;
 
-	// TODO check ranges
-
-	printf("oberon_make_array_selector: index class %i\n", index -> result -> class);
 	if(index -> result -> class != OBERON_TYPE_INTEGER)
 	{
 		oberon_error(ctx, "index must be integer");
 	}
 
-	if(index -> is_item)
+	// Статическая проверка границ массива
+	if(desig -> result -> size != 0)
 	{
-		if(index -> item.mode == MODE_INTEGER)
+		if(index -> is_item)
 		{
-			int arr_size = desig -> result -> size;
-			int index_int = index -> item.integer;
-			if(index_int < 0 || index_int > arr_size - 1)
+			if(index -> item.mode == MODE_INTEGER)
 			{
-				oberon_error(ctx, "not in range (dimension size 0..%i)", arr_size - 1);
+				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);
+				}
 			}
 		}
 	}
 
 	oberon_expr_t * selector;
-	selector = oberon_new_item(MODE_INDEX, base);
+	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;
@@ -840,8 +1069,25 @@ oberon_make_record_selector(oberon_context_t * ctx, oberon_expr_t * expr, char *
 	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);
+	selector = oberon_new_item(MODE_FIELD, field -> type, read_only);
 	selector -> item.var = field;
 	selector -> item.parent = (oberon_item_t *) expr;
 
@@ -853,6 +1099,39 @@ oberon_make_record_selector(oberon_context_t * ctx, oberon_expr_t * expr, char *
 	|| ((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)
 {
@@ -860,8 +1139,16 @@ oberon_designator(oberon_context_t * ctx)
 	oberon_object_t * var;
 	oberon_expr_t * expr;
 
-	name = oberon_assert_ident(ctx);
-	var = oberon_find_object(ctx -> decl, name, 1);
+	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)
 	{
@@ -872,10 +1159,10 @@ oberon_designator(oberon_context_t * ctx)
 		case OBERON_CLASS_VAR:
 		case OBERON_CLASS_VAR_PARAM:
 		case OBERON_CLASS_PARAM:
-			expr = oberon_new_item(MODE_VAR, var -> type);
+			expr = oberon_new_item(MODE_VAR, var -> type, read_only);
 			break;
 		case OBERON_CLASS_PROC:
-			expr = oberon_new_item(MODE_CALL, var -> type);
+			expr = oberon_new_item(MODE_VAR, var -> type, 1);
 			break;
 		default:
 			oberon_error(ctx, "invalid designator");
@@ -918,17 +1205,13 @@ oberon_designator(oberon_context_t * ctx)
 }
 
 static oberon_expr_t *
-oberon_opt_proc_parens(oberon_context_t * ctx, oberon_expr_t * expr)
+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)
 	{
-		if(expr -> result -> class != OBERON_TYPE_PROCEDURE)
-		{
-			oberon_error(ctx, "not a procedure");
-		}
-
 		oberon_assert_token(ctx, LPAREN);
 
 		int num_args = 0;
@@ -939,18 +1222,38 @@ oberon_opt_proc_parens(oberon_context_t * ctx, oberon_expr_t * expr)
 			oberon_expr_list(ctx, &num_args, &arguments, 0);
 		}
 
-		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);
+		expr = oberon_make_call_func(ctx, expr -> item.var, num_args, arguments);
 
-		oberon_autocast_call(ctx, expr);
+		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)
 {
@@ -960,20 +1263,25 @@ oberon_factor(oberon_context_t * ctx)
 	{
 		case IDENT:
 			expr = oberon_designator(ctx);
-			expr = oberon_opt_proc_parens(ctx, expr);
+			expr = oberon_opt_func_parens(ctx, expr);
 			break;
 		case INTEGER:
-			expr = oberon_new_item(MODE_INTEGER, ctx -> int_type);
+			expr = oberon_new_item(MODE_INTEGER, ctx -> int_type, 1);
 			expr -> item.integer = ctx -> integer;
 			oberon_assert_token(ctx, INTEGER);
 			break;
+		case REAL:
+			expr = oberon_new_item(MODE_REAL, ctx -> real_type, 1);
+			expr -> item.real = ctx -> real;
+			oberon_assert_token(ctx, REAL);
+			break;
 		case TRUE:
-			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type);
+			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);
+			expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type, 1);
 			expr -> item.boolean = 0;
 			oberon_assert_token(ctx, FALSE);
 			break;
@@ -989,7 +1297,7 @@ oberon_factor(oberon_context_t * ctx)
 			break;
 		case NIL:
 			oberon_assert_token(ctx, NIL);
-			expr = oberon_new_item(MODE_NIL, ctx -> void_ptr_type);
+			expr = oberon_new_item(MODE_NIL, ctx -> void_ptr_type, 1);
 			break;
 		default:
 			oberon_error(ctx, "invalid expression");
@@ -1106,6 +1414,46 @@ oberon_make_bin_op(oberon_context_t * ctx, int token, oberon_expr_t * a, oberon_
 			oberon_error(ctx, "oberon_make_bin_op: bool wat");
 		}
 	}
+	else if(token == SLASH)
+	{
+		if(a -> result -> class != OBERON_TYPE_REAL)
+		{
+			if(a -> result -> class == OBERON_TYPE_INTEGER)
+			{
+				oberon_error(ctx, "TODO cast int -> real");
+			}
+			else
+			{
+				oberon_error(ctx, "operator / requires numeric type");
+			}
+		}
+
+		if(b -> result -> class != OBERON_TYPE_REAL)
+		{
+			if(b -> result -> class == OBERON_TYPE_INTEGER)
+			{
+				oberon_error(ctx, "TODO cast int -> real");
+			}
+			else
+			{
+				oberon_error(ctx, "operator / requires numeric type");
+			}
+		}
+
+		oberon_autocast_binary_op(ctx, a -> result, b -> result, &result);
+		expr = oberon_new_operator(OP_DIV, result, a, b);
+	}
+	else if(token == DIV)
+	{
+		if(a -> result -> class != OBERON_TYPE_INTEGER
+			|| b -> result -> class != OBERON_TYPE_INTEGER)
+		{
+			oberon_error(ctx, "operator DIV requires integer type");
+		}
+
+		oberon_autocast_binary_op(ctx, a -> result, b -> result, &result);
+		expr = oberon_new_operator(OP_DIV, result, a, b);
+	}
 	else
 	{
 		oberon_autocast_binary_op(ctx, a -> result, b -> result, &result);
@@ -1122,14 +1470,6 @@ oberon_make_bin_op(oberon_context_t * ctx, int token, oberon_expr_t * a, oberon_
 		{
 			expr = oberon_new_operator(OP_MUL, result, a, b);
 		}
-		else if(token == SLASH)
-		{
-			expr = oberon_new_operator(OP_DIV, result, a, b);
-		}
-		else if(token == DIV)
-		{
-			expr = oberon_new_operator(OP_DIV, result, a, b);
-		}
 		else if(token == MOD)
 		{
 			expr = oberon_new_operator(OP_MOD, result, a, b);
@@ -1241,7 +1581,9 @@ 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)
@@ -1269,50 +1611,88 @@ oberon_assert_ident(oberon_context_t * ctx)
 }
 
 static void
-oberon_var_decl(oberon_context_t * ctx)
+oberon_def(oberon_context_t * ctx, int * export, int * read_only)
+{
+	switch(ctx -> token)
+	{
+		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;
-	oberon_type_t * type;
-	type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+	int export;
+	int read_only;
+	oberon_object_t * x;
 
 	name = oberon_assert_ident(ctx);
-	oberon_assert_token(ctx, COLON);
-	oberon_type(ctx, &type);
-	oberon_define_var(ctx -> decl, OBERON_CLASS_VAR, name, type);
+	oberon_def(ctx, &export, &read_only);
+
+	x = oberon_define_object(ctx -> decl, name, class, export, read_only);
+	return x;
 }
 
-static oberon_object_t *
-oberon_make_param(oberon_context_t * ctx, int token, char * name, oberon_type_t * type)
+static void
+oberon_ident_list(oberon_context_t * ctx, int class, int * num, oberon_object_t ** list)
 {
-	oberon_object_t * param;
-
-	if(token == VAR)
-	{
-		param = oberon_define_var(ctx -> decl, OBERON_CLASS_VAR_PARAM, name, type);
-	}
-	else if(token == IDENT)
+	*num = 1;
+	*list = oberon_ident_def(ctx, class);
+	while(ctx -> token == COMMA)
 	{
-		param = oberon_define_var(ctx -> decl, OBERON_CLASS_PARAM, name, type);
+		oberon_assert_token(ctx, COMMA);
+		oberon_ident_def(ctx, class);
+		*num += 1;
 	}
-	else
+}
+
+static void
+oberon_var_decl(oberon_context_t * ctx)
+{
+	int num;
+	oberon_object_t * list;
+	oberon_type_t * type;
+	type = oberon_new_type_ptr(OBERON_TYPE_VOID);
+
+	oberon_ident_list(ctx, OBERON_CLASS_VAR, &num, &list);
+	oberon_assert_token(ctx, COLON);
+	oberon_type(ctx, &type);
+
+	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);
 
@@ -1320,11 +1700,15 @@ oberon_fp_section(oberon_context_t * ctx, int * num_decl)
 	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 \
@@ -1350,7 +1734,14 @@ oberon_formal_pars(oberon_context_t * ctx, oberon_type_t * signature)
 	if(ctx -> token == COLON)
 	{
 		oberon_assert_token(ctx, COLON);
-		oberon_type(ctx, &signature -> base);
+
+		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;
 	}
 }
 
@@ -1364,16 +1755,47 @@ oberon_opt_formal_pars(oberon_context_t * ctx, oberon_type_t ** type)
 	signature -> base = ctx -> void_type;
 	signature -> decl = NULL;
 
-	if(ctx -> token == LPAREN)
+	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");
+	}
+
+	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++)
 	{
-		oberon_formal_pars(ctx, signature);
+		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)
 		{
@@ -1387,41 +1809,25 @@ 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;
-	signature = oberon_new_type_ptr(OBERON_TYPE_VOID);
-	oberon_opt_formal_pars(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);
@@ -1429,39 +1835,107 @@ 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;
 }
 
@@ -1490,14 +1964,23 @@ oberon_field_list(oberon_context_t * ctx, oberon_type_t * rec)
 {
 	if(ctx -> token == IDENT)
 	{
-		char * name;
+		int num;
+		oberon_object_t * list;
 		oberon_type_t * type;
 		type = oberon_new_type_ptr(OBERON_TYPE_VOID);
 
-		name = oberon_assert_ident(ctx);
+		oberon_ident_list(ctx, OBERON_CLASS_FIELD, &num, &list);
 		oberon_assert_token(ctx, COLON);
 		oberon_type(ctx, &type);
-		oberon_define_field(ctx, rec, name, type);
+
+		oberon_object_t * field = list;
+		for(int i = 0; i < num; i++)
+		{
+			field -> type = type;
+			field = field -> next;
+		}
+
+		rec -> num_decl += num;
 	}
 }
 
@@ -1507,8 +1990,10 @@ oberon_qualident_type(oberon_context_t * ctx, oberon_type_t ** type)
 	char * name;
 	oberon_object_t * to;
 
-	name = oberon_assert_ident(ctx);
-	to = oberon_find_object(ctx -> decl, name, 0);
+	to = oberon_qualident(ctx, &name, 0);
+
+	//name = oberon_assert_ident(ctx);
+	//to = oberon_find_object(ctx -> decl, name, 0);
 
 	if(to != NULL)
 	{
@@ -1519,7 +2004,7 @@ oberon_qualident_type(oberon_context_t * ctx, oberon_type_t ** type)
 	}
 	else
 	{
-		to = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE);
+		to = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE, 0, 0);
 		to -> type = oberon_new_type_ptr(OBERON_TYPE_VOID);
 	}
 
@@ -1549,6 +2034,14 @@ oberon_make_multiarray(oberon_context_t * ctx, oberon_expr_t * sizes, oberon_typ
 	oberon_make_array_type(ctx, sizes, dim, type);
 }
 
+static void
+oberon_make_open_array(oberon_context_t * ctx, oberon_type_t * base, oberon_type_t * type)
+{
+	type -> class = OBERON_TYPE_ARRAY;
+	type -> size = 0;
+	type -> base = base;
+}
+
 static void
 oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
 {
@@ -1562,7 +2055,11 @@ oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
 
 		int num_sizes = 0;
 		oberon_expr_t * sizes;
-		oberon_expr_list(ctx, &num_sizes, &sizes, 1);
+
+		if(ISEXPR(ctx -> token))
+		{
+			oberon_expr_list(ctx, &num_sizes, &sizes, 1);
+		}
 
 		oberon_assert_token(ctx, OF);
 
@@ -1570,18 +2067,26 @@ oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
 		base = oberon_new_type_ptr(OBERON_TYPE_VOID);
 		oberon_type(ctx, &base);
 
-		oberon_make_multiarray(ctx, sizes, base, type);
+		if(num_sizes == 0)
+		{
+			oberon_make_open_array(ctx, base, *type);
+		}
+		else
+		{
+			oberon_make_multiarray(ctx, sizes, base, type);
+		}
 	}
 	else if(ctx -> token == RECORD)
 	{
 		oberon_type_t * rec;
 		rec = *type;
 		rec -> class = OBERON_TYPE_RECORD;
-		oberon_object_t * list = malloc(sizeof *list);
-	        memset(list, 0, sizeof *list);
-		rec -> num_decl = 0;
-		rec -> base = NULL;
-		rec -> decl = list;
+
+		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);
@@ -1592,7 +2097,9 @@ oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
 		}
 		oberon_assert_token(ctx, END);
 
-		rec -> decl = rec -> decl -> next;
+		rec -> decl = record_scope -> list -> next;
+		oberon_close_scope(record_scope);
+
 		*type = rec;
 	}
 	else if(ctx -> token == POINTER)
@@ -1628,13 +2135,16 @@ 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);
+		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);
 	}
@@ -1649,6 +2159,9 @@ oberon_type_decl(oberon_context_t * ctx)
 		{
 			oberon_error(ctx, "mult definition - already linked");
 		}
+
+		newtype -> export = export;
+		newtype -> read_only = read_only;
 	}
 
 	oberon_assert_token(ctx, EQUAL);
@@ -1800,6 +2313,7 @@ oberon_prevent_recursive_object(oberon_context_t * ctx, oberon_object_t * x)
 			break;
 		case OBERON_CLASS_CONST:
 		case OBERON_CLASS_PROC:
+		case OBERON_CLASS_MODULE:
 			break;
 		default:
 			oberon_error(ctx, "oberon_prevent_recursive_object: wat");
@@ -1868,6 +2382,17 @@ oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type)
 	}
 	else if(type -> class == OBERON_TYPE_ARRAY)
 	{
+		if(type -> size != 0)
+		{
+			if(type -> base -> class == OBERON_TYPE_ARRAY)
+			{
+				if(type -> base -> size == 0)
+				{
+					oberon_error(ctx, "open array not allowed as array element");
+				}
+			}
+		}
+
 		oberon_initialize_type(ctx, type -> base);		
 		oberon_generator_init_type(ctx, type);
 	}
@@ -1897,24 +2422,41 @@ oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type)
 static void
 oberon_initialize_object(oberon_context_t * ctx, oberon_object_t * x)
 {
-	printf("oberon_initialize_object: name %s class %i\n", x -> name, x -> class);
+	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_FIELD:
+			if(x -> type -> class == OBERON_TYPE_ARRAY)
+			{
+				if(x -> type -> size == 0)
+				{
+					oberon_error(ctx, "open array not allowed as variable or field");
+				}
+			}
+			oberon_initialize_type(ctx, x -> type);
+			oberon_generator_init_var(ctx, x);
+			break;
 		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_prevent_recursive_object: wat");
+			oberon_error(ctx, "oberon_initialize_object: wat");
 			break;
 	}
 }
@@ -1931,6 +2473,24 @@ oberon_initialize_decl(oberon_context_t * ctx)
 	}	
 }
 
+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
 oberon_decl_seq(oberon_context_t * ctx)
 {
@@ -1972,22 +2532,22 @@ oberon_decl_seq(oberon_context_t * ctx)
 		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)
 {
@@ -2005,8 +2565,7 @@ 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)
@@ -2036,10 +2595,74 @@ 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);
@@ -2047,15 +2670,20 @@ 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);
@@ -2082,25 +2710,153 @@ register_default_types(oberon_context_t * ctx)
 	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(bool));
+	oberon_define_type(ctx -> world_scope, "BOOLEAN", ctx -> bool_type, 1);
+
+	ctx -> real_type = oberon_new_type_real(sizeof(float));
+	oberon_define_type(ctx -> world_scope, "REAL", ctx -> real_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");
+	}
+
+	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;
+	src = oberon_new_item(MODE_NEW, dst -> result, 0);
+	src -> item.num_args = 0;
+	src -> item.args = NULL;
+
+	int max_args = 1;
+	if(type -> class == OBERON_TYPE_ARRAY)
+	{
+		if(type -> size == 0)
+		{
+			oberon_type_t * x = type;
+			while(x -> class == OBERON_TYPE_ARRAY)
+			{
+				if(x -> size == 0)
+				{
+					max_args += 1;
+				}
+				x = x -> base;
+			}
+		}
+
+		if(num_args < max_args)
+		{
+			oberon_error(ctx, "too few arguments");
+		}
+
+		if(num_args > max_args)
+		{
+			oberon_error(ctx, "too mach arguments");
+		}
+
+		int num_sizes = max_args - 1;
+		oberon_expr_t * size_list = list_args -> next;
+
+		oberon_expr_t * arg = size_list;
+		for(int i = 0; i < max_args - 1; i++)
+		{
+			if(arg -> result -> class != OBERON_TYPE_INTEGER)
+			{
+				oberon_error(ctx, "size must be integer");
+			}
+			arg = arg -> next;
+		}
+
+		src -> item.num_args = num_sizes;
+		src -> item.args = size_list;
+	}
+	else if(type -> class != OBERON_TYPE_RECORD)
+	{
+		oberon_error(ctx, "oberon_make_new_call: wat");
+	}
+
+	if(num_args > max_args)
+	{
+		oberon_error(ctx, "too mach arguments");
+	}
 
-	ctx -> bool_type = oberon_new_type_boolean(sizeof(int));
-	oberon_define_type(ctx -> world_scope, "BOOLEAN", ctx -> bool_type);
+	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;
 }
@@ -2113,21 +2869,41 @@ 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;
 }