Using bind1st for a method that takes argument by reference

std::bind1st and std::bind2nd don't accept functors which take reference arguments, because they themselves form references to these arguments. You can

1. use pointers for your function inputs instead of references
2. use boost::bind
3. accept the performance cost of copying the string

The issue is a defect in the library specification.

Take a look at this bug report against gcc and the resulting discussion: Bug 37811 - bind1st fails on mem_fun with reference argument

C++03 lacked the facilities to build a perfect bind library. This issue is fixed in C++11 with perfect forwarding and std::bind.