# V655\. Strings were concatenated but not used\. Consider inspecting the expression\.

The analyzer has detected a potential error: an unused concatenation of string variables in the code was found\. The types of these variables are as follows: std::string, CString, QString, wxString\. These expressions most often appear in the code when an assignment operator is missing or as a result of careless code refactoring\.

Consider the following sample of incorrect code:

```cpp
void Foo(std::string &s1, const std::string &s2)
{
  s1 + s2;
}
```

The code contains a misprint: '\+' is written instead of '\+\='\. The code compiles well but is senseless\. This is the fixed code:

```cpp
void Foo(std::string &s1, const std::string &s2)
{
  s1 += s2;
}
```