diff --git a/HISTORY b/HISTORY
index cd18e41..9ff9415 100755
--- a/HISTORY
+++ b/HISTORY
@@ -1,3 +1,7 @@
+May. 6 2015
+Removed redundant EOS tokens
+Polished data precision related macros
+
 May. 5 2015
 Added string type support for non-simple array
 Fixed a memory leak when storing strings to a non-string array
diff --git a/core/my_basic.c b/core/my_basic.c
index feb265a..1c92653 100755
--- a/core/my_basic.c
+++ b/core/my_basic.c
@@ -78,7 +78,7 @@ extern "C" {
 /** Macros */
 #define _VER_MAJOR 1
 #define _VER_MINOR 1
-#define _VER_REVISION 53
+#define _VER_REVISION 54
 #define _MB_VERSION ((_VER_MAJOR * 0x01000000) + (_VER_MINOR * 0x00010000) + (_VER_REVISION))
 
 /* Uncomment this line to treat warnings as error */
@@ -1939,6 +1939,12 @@ int _create_symbol(mb_interpreter_t* s, _ls_node_t* l, char* sym, _object_t** ob
 	type = _get_symbol_type(s, sym, &value);
 	(*obj)->type = type;
 	switch(type) {
+	case _DT_NIL:
+		safe_free(*obj);
+		*obj = 0;
+		safe_free(sym);
+
+		break;
 	case _DT_INT:
         memcpy(tmp.any, value, sizeof(_raw_t));
 		(*obj)->data.integer = tmp.integer;
@@ -2083,7 +2089,7 @@ _data_e _get_symbol_type(mb_interpreter_t* s, char* sym, _raw_t* value) {
 	context = s->parsing_context;
 
 	/* int_t */
-	tmp.integer = (int_t)strtol(sym, &conv_suc, 0);
+	tmp.integer = (int_t)mb_strtol(sym, &conv_suc, 0);
 	if(*conv_suc == '\0') {
         memcpy(*value, tmp.any, sizeof(_raw_t));
 
@@ -2092,7 +2098,7 @@ _data_e _get_symbol_type(mb_interpreter_t* s, char* sym, _raw_t* value) {
 		goto _exit;
 	}
 	/* real_t */
-	tmp.float_point = (real_t)strtod(sym, &conv_suc);
+	tmp.float_point = (real_t)mb_strtod(sym, &conv_suc);
 	if(*conv_suc == '\0') {
         memcpy(*value, tmp.any, sizeof(_raw_t));
 
@@ -2155,7 +2161,10 @@ _data_e _get_symbol_type(mb_interpreter_t* s, char* sym, _raw_t* value) {
 	}
 	/* MB_EOS */
 	if(_sl == 1 && sym[0] == MB_EOS) {
-		result = _DT_EOS;
+		if(_IS_EOS(context->last_symbol))
+			result = _DT_NIL;
+		else
+			result = _DT_EOS;
 
 		goto _exit;
 	}
@@ -3779,7 +3788,7 @@ int mb_dispose_value(struct mb_interpreter_t* s, mb_value_t val) {
 	mb_assert(s);
 
 	if(val.type == MB_DT_STRING)
-		mb_free(val.value.string);
+		safe_free(val.value.string);
 
 	return result;
 }
@@ -3863,7 +3872,7 @@ int mb_load_file(struct mb_interpreter_t* s, const char* f) {
 		buf[l] = '\0';
 
 		result = mb_load_string(s, buf);
-		mb_free(buf);
+		safe_free(buf);
 
 		if(result)
 			goto _exit;
@@ -5977,14 +5986,14 @@ int _std_val(mb_interpreter_t* s, void** l) {
 
 	mb_check(mb_attempt_close_bracket(s, l));
 
-	val.value.integer = (int_t)strtol(arg, &conv_suc, 0);
+	val.value.integer = (int_t)mb_strtol(arg, &conv_suc, 0);
 	if(*conv_suc == '\0') {
 		val.type = MB_DT_INT;
 		mb_check(mb_push_value(s, l, val));
 
 		goto _exit;
 	}
-	val.value.float_point = (real_t)strtod(arg, &conv_suc);
+	val.value.float_point = (real_t)mb_strtod(arg, &conv_suc);
 	if(*conv_suc == '\0') {
 		val.type = MB_DT_REAL;
 		mb_check(mb_push_value(s, l, val));
@@ -6107,10 +6116,10 @@ int _std_input(mb_interpreter_t* s, void** l) {
 	if(obj->data.variable->data->type == _DT_INT || obj->data.variable->data->type == _DT_REAL) {
 		_get_inputer(s)(line, sizeof(line));
 		obj->data.variable->data->type = _DT_INT;
-		obj->data.variable->data->data.integer = (int_t)strtol(line, &conv_suc, 0);
+		obj->data.variable->data->data.integer = (int_t)mb_strtol(line, &conv_suc, 0);
 		if(*conv_suc != '\0') {
 			obj->data.variable->data->type = _DT_REAL;
-			obj->data.variable->data->data.float_point = (real_t)strtod(line, &conv_suc);
+			obj->data.variable->data->data.float_point = (real_t)mb_strtod(line, &conv_suc);
 			if(*conv_suc != '\0') {
 				result = MB_FUNC_ERR;
 
diff --git a/core/my_basic.h b/core/my_basic.h
index fc9f5d2..31277e1 100755
--- a/core/my_basic.h
+++ b/core/my_basic.h
@@ -75,6 +75,13 @@ extern "C" {
 #	define real_t float
 #endif
 
+#ifndef mb_strtol
+#	define mb_strtol(__s, __e, __r) strtol((__s), (__e), (__r))
+#endif
+#ifndef mb_strtod
+#	define mb_strtod(__s, __e) strtod((__s), (__e))
+#endif
+
 #ifndef MB_INT_FMT
 #	define MB_INT_FMT "%d"
 #endif
diff --git a/output/my_basic.exe b/output/my_basic.exe
index 4868a73..f78645e 100755
Binary files a/output/my_basic.exe and b/output/my_basic.exe differ
diff --git a/output/my_basic_mac b/output/my_basic_mac
index aee967f..48f7a5f 100755
Binary files a/output/my_basic_mac and b/output/my_basic_mac differ
diff --git a/resource/my_basic.rc b/resource/my_basic.rc
index 41149be..ae81208 100755
--- a/resource/my_basic.rc
+++ b/resource/my_basic.rc
@@ -36,8 +36,8 @@
 	IDI_ICON_MAIN ICON "icon.ico"
 
 	VS_VERSION_INFO VERSIONINFO
-	FILEVERSION 1,1,53,0
-	PRODUCTVERSION 1,1,53,0
+	FILEVERSION 1,1,54,0
+	PRODUCTVERSION 1,1,54,0
 	FILEFLAGSMASK 0x17L
 #	ifdef _DEBUG
 	FILEFLAGS 0x1L
@@ -55,13 +55,13 @@
 				VALUE "Comments", "MY-BASIC"
 				VALUE "CompanyName", "W. Renxin"
 				VALUE "FileDescription", "MY-BASIC interpreter"
-				VALUE "FileVersion", "1, 1, 53, 0"
+				VALUE "FileVersion", "1, 1, 54, 0"
 				VALUE "InternalName", "my_basic"
 				VALUE "LegalCopyright", "Copyright (C) 2011 - 2015 W. Renxin"
 				VALUE "LegalTrademarks", "MY-BASIC"
 				VALUE "OriginalFilename", "my_basic.exe"
 				VALUE "ProductName", "MY-BASIC"
-				VALUE "ProductVersion", "1, 1, 53, 0"
+				VALUE "ProductVersion", "1, 1, 54, 0"
 			END
 		END
 		BLOCK "VarFileInfo"