Boost C++ Application Development Cookbook - Second Edition

How it works...

The boost::format class accepts the string that specifies the resulting string format. Arguments are passed to boost::format using operator%. Values %1%, %2%, %3%, %4%, and so on, in the format specifying string are replaced by arguments passed to boost::format.

We also disable the exceptions for cases when a format string contains fewer arguments than passed to boost::format:

    boost::format f(format_specifier);    unsigned char flags = boost::io::all_error_bits;    flags ^= boost::io::too_many_args_bit;

This is done to allow some formats like this:

    // Outputs 'Reader'.    std::cout << class_instance.to_string("%2%\n\n");