*fixed a bug with nested if statement; *fixed an indexing bug with list; +added a new sample script source file.

HISTORY

@@ -1,5 +1,8 @@
 Jan. 25 2016
 Fixed a memory leak when printing a referenced usertype
+Fixed a bug with nested IF statement
+Fixed an indexing bug with list
+Added a new sample script source file
 
 Jan. 23 2016
 Added lazy evaluation for ranged list
@@ -283,8 +286,8 @@ Improved memory pool
 
 Oct. 11 2015
 Added a CLONE statement/function for collections
-Optimized LIST indexing
-Optimized LIST counting
+Optimized list indexing
+Optimized list counting
 
 Oct. 10 2015
 Improved stability for nested IF statement

core/my_basic.c

@@ -6108,7 +6108,7 @@ _ls_node_t* _node_at_list(_list_t* coll, int index) {
 					coll->cached_index++;
 				} else if(index < coll->cached_index) {
 					coll->cached_node = coll->cached_node->prev;
-					coll->cached_node--;
+					coll->cached_index--;
 				}
 			}
 			result = coll->cached_node;
@@ -12082,6 +12082,7 @@ int _core_if(mb_interpreter_t* s, void** l) {
 	_object_t* val = 0;
 	_object_t* obj = 0;
 	bool_t multi_line = false;
+	bool_t skip = false;
 	_running_context_t* running = 0;
 
 	mb_assert(s && l);
@@ -12101,6 +12102,8 @@ _elseif:
 
 	obj = (_object_t*)ast->data;
 	if(val->data.integer) {
+		skip = true;
+
 		if(!_IS_FUNC(obj, _core_then)) {
 			_handle_error_on_obj(s, SE_RN_INTEGER_EXPECTED, s->source_file, DON(ast), MB_FUNC_ERR, _exit, result);
 		}
@@ -12113,6 +12116,11 @@ _elseif:
 			ast = ast->next;
 			while(ast && _IS_EOS(ast->data))
 				ast = ast->next;
+			if(ast && _IS_FUNC(ast->data, _core_endif)) {
+				ast = ast->prev;
+
+				break;
+			}
 			result = _execute_statement(s, &ast);
 			if(result != MB_FUNC_OK)
 				goto _exit;
@@ -12159,6 +12167,8 @@ _elseif:
 
 		obj = (_object_t*)ast->data;
 		if(obj->type != _DT_EOS) {
+			skip = true;
+
 			if(!_IS_FUNC(obj, _core_else)) {
 				_handle_error_on_obj(s, SE_RN_ELSE_EXPECTED, s->source_file, DON(ast), MB_FUNC_ERR, _exit, result);
 			}
@@ -12167,6 +12177,11 @@ _elseif:
 				ast = ast->next;
 				while(_IS_EOS(ast->data))
 					ast = ast->next;
+				if(ast && _IS_FUNC(ast->data, _core_endif)) {
+					ast = ast->prev;
+
+					break;
+				}
 				result = _execute_statement(s, &ast);
 				if(result != MB_FUNC_OK)
 					goto _exit;
@@ -12184,8 +12199,10 @@ _exit:
 	if(result == MB_SUB_RETURN) {
 		ast = ast->prev;
 	} else {
-		if(multi_line)
-			result = _skip_to(s, &ast, _core_endif, _DT_NIL);
+		if(multi_line) {
+			if(skip)
+				result = _skip_struct(s, &ast, _core_if, _core_endif);
+		}
 	}
 
 	*l = ast;

my_basic.vcproj

@@ -329,6 +329,26 @@
 					/>
 				</FileConfiguration>
 			</File>
+			<File
+				RelativePath=".\sample\sample07.bas"
+				>
+				<FileConfiguration
+					Name="debug|Win32"
+					ExcludedFromBuild="true"
+					>
+					<Tool
+						Name="VCCustomBuildTool"
+					/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="release|Win32"
+					ExcludedFromBuild="true"
+					>
+					<Tool
+						Name="VCCustomBuildTool"
+					/>
+				</FileConfiguration>
+			</File>
 		</Filter>
 		<Filter
 			Name="res"

sample/sample07.bas

@@ -0,0 +1,84 @@
+' This script is an example of MY-BASIC
+' Copyright (c) 2011 - 2016 Wang Renxin. All rights reserved.
+' For more information, see https://github.com/paladin-t/my_basic/
+
+def reserve(m, n)
+	for j = len(m) to n + 2
+		push(m, 0)
+	next
+enddef
+
+def forward(cmd, i)
+	l = len(cmd)
+	while i < l and mid(cmd, i, 1) <> "]"
+		i = i + 1
+	wend
+	if i < l then
+		i = i + 1
+	endif
+
+	return i
+enddef
+
+def backward(cmd, i)
+	while i > 0 and mid(cmd, i, 1) <> "["
+		i = i - 1
+	wend
+	if i > 0 then
+		i = i - 1
+	endif
+
+	return i
+enddef
+
+def brainfuck(cmd)
+	m = list()
+
+	i = 0
+	cursor = 0
+
+	l = len(cmd)
+	while i < l
+		c = mid(cmd, i, 1)
+		if c = ">" then
+			cursor = cursor + 1
+		elseif c = "<" then
+			cursor = cursor - 1
+		elseif c = "+" then
+			reserve(m, cursor)
+			b = m(cursor)
+			m(cursor) = b + 1
+		elseif c = "-" then
+			reserve(m, cursor)
+			b = m(cursor)
+			m(cursor) = b - 1
+		elseif c = "." then
+			reserve(m, cursor)
+			print chr(m(cursor))
+		elseif c = "," then
+			reserve(m, cursor)
+			input ch$
+			m(cursor) = asc(ch$)
+		elseif c = "[" then
+			reserve(m, cursor)
+			b = m(cursor)
+			if b = 0 then
+				i = forward(cmd, i)
+			endif
+		elseif c = "]" then
+			reserve(m, cursor)
+			b = m(cursor)
+			if b <> 0 then
+				i = backward(cmd, i)
+			endif
+		endif
+		i = i + 1
+	wend
+enddef
+
+' This is a brainfuck interpreter written with MY-BASIC
+' Try this code (without brackets): "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>."
+print "BF: "
+input cmd$
+
+brainfuck(cmd$)