diff --git a/HISTORY b/HISTORY
index 0bf6670..34127a7 100755
--- a/HISTORY
+++ b/HISTORY
@@ -1,5 +1,8 @@
+May. 24 2016
+Refactored error raising of string manipulation
+
 May. 20 2016
-Added an assertion when buffer overflow in STR
+Added an assertion when buffer overflow in the STR statement
 
 May. 19 2016
 Added UTF8 BOM detection even with MB_ENABLE_UNICODE disabled
diff --git a/core/my_basic.c b/core/my_basic.c
index fb048fb..9d594ef 100755
--- a/core/my_basic.c
+++ b/core/my_basic.c
@@ -14997,9 +14997,7 @@ static int _std_left(mb_interpreter_t* s, void** l) {
 	mb_check(mb_attempt_close_bracket(s, l));
 
 	if(count <= 0) {
-		result = MB_FUNC_ERR;
-
-		goto _exit;
+		_handle_error_on_obj(s, SE_RN_INDEX_OUT_OF_BOUND, s->source_file, DON2(l), MB_FUNC_ERR, _exit, result);
 	}
 
 #ifdef MB_ENABLE_UNICODE
@@ -15043,9 +15041,7 @@ static int _std_mid(mb_interpreter_t* s, void** l) {
 	mb_check(mb_attempt_close_bracket(s, l));
 
 	if(count <= 0 || start < 0 || start >= (int_t)strlen(arg)) {
-		result = MB_FUNC_ERR;
-
-		goto _exit;
+		_handle_error_on_obj(s, SE_RN_INDEX_OUT_OF_BOUND, s->source_file, DON2(l), MB_FUNC_ERR, _exit, result);
 	}
 
 #ifdef MB_ENABLE_UNICODE
@@ -15087,9 +15083,7 @@ static int _std_right(mb_interpreter_t* s, void** l) {
 	mb_check(mb_attempt_close_bracket(s, l));
 
 	if(count <= 0) {
-		result = MB_FUNC_ERR;
-
-		goto _exit;
+		_handle_error_on_obj(s, SE_RN_INDEX_OUT_OF_BOUND, s->source_file, DON2(l), MB_FUNC_ERR, _exit, result);
 	}
 
 #ifdef MB_ENABLE_UNICODE
diff --git a/output/my_basic.exe b/output/my_basic.exe
index 86d9ca2..428425f 100755
Binary files a/output/my_basic.exe and b/output/my_basic.exe differ