diff --git a/src/tabs.cpp b/src/tabs.cpp
index 693bc5f..5899f01 100644
--- a/src/tabs.cpp
+++ b/src/tabs.cpp
@@ -145,27 +145,50 @@ int brackets;
 }
 
 
+bool IsWhite(int c)
+{
+	return c==' ' || c=='\t';
+}
+
+
+bool IsOpeningOperand(int c)
+{
+	return c=='-' || c=='+' || c=='*' ||c=='/' || c=='%' ||c=='^' || c=='(';
+}
+
+
+bool IsOpeningOperandBefore(const char * buf, int end)
+{
+	while( end > 0 && IsWhite(buf[end-1]) )
+		end -= 1;
+
+	if( end == 0 )
+		return false;
+
+return IsOpeningOperand(buf[end-1]);
+}
+
+
+
 void CalcBracketsPos(HWND input, int & start, int & end)
 {
 DWORD sel_start, sel_end;
 
 	SendMessage(input, EM_GETSEL, (WPARAM)&sel_start, (LPARAM)&sel_end);
 
-	if( sel_start != sel_end )
-	{	
-		start = sel_start;
-		end   = sel_end;
+	start = sel_start;
+	end   = sel_end;
+
+	if( start != end )
 		return;
-	}
 
 	char * buf = GetPrgRes()->GetBufferTemp();
-	start      = 0;
-	end        = SendMessage(input, WM_GETTEXT, GetPrgRes()->GetBufferSize(), (LPARAM)buf);
+	int len = SendMessage(input, WM_GETTEXT, GetPrgRes()->GetBufferSize(), (LPARAM)buf);
 
-	if( end > 0 )
+	if( len > 0 && !IsOpeningOperandBefore(buf, end) )
 	{
 		start = CalcBracketsPrev(buf, sel_start);
-		end   = CalcBracketsNext(buf, end, sel_start);
+		end   = CalcBracketsNext(buf, len, sel_start);
 	}
 }