error: expected initializer before ‘:’ token

c++, linux, porting

Solution

Your compiler is too old to support range-based `for` syntax. According to GNU it was first supported in GCC 4.6. GCC also requires you to explicitly request C++11 support, by giving the command-line option `-std=c++11`, or `c++0x` on compilers as old as yours.

If you can't upgrade, then you'll need the old-school equivalent:

for (auto it = inNwsFile.begin(); it != inNwsFile.end(); ++it) {
    std::string const &nwFile = *it; // const needed because inNwsFile is const
    //some...
}

I believe `auto` is available in GCC 4.4 (as long as you enable C++0x support), to save you writing `std::vector<string>::const_iterator`.

If you really do need a non-`const` reference to the vector's elements then, whichever style of loop you use, you'll need to remove the `const` from the function parameter.

Problem

I am trying to compile some C++ code (which can be compiled with Visual Studio 2012 on Windows) with `g++-4.4`. I have this snippet of code, ``` const std::string cnw::restoreSession(const std::vector<string> &inNwsFile) { for (std::string &nwFile : inNwsFile){ // some... } } ``` that I cannot compile because of this error: ``` CNWController.cpp:154: error: expected initializer before ‘:’ token ``` Can you give me some advise on how to solve this problem?

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