As, below, there's a new statement: '_Generic()'. The expression looks like this:

    _Generic(x, type : value, ..., [default : value])

For a list of unique types, with an optional 'default' for any unrecognized type.

You usually wrap the call to '_Generic' in a macro. For instance:

    #define vec_push_back(vec, val) \
        _Generic(&vec, \
        vecint : vecint_push_back, \
        vecdbl : vecdbl_push_back, \
        default : assert_vwrap)(&vec, val)

Assuming that types 'vecint' and 'vecdbl' have been defined by the user. This does single-parameter parametric type dispatch. There's way to allow the user to use table-driven macros ('X-macros') to allow per-translation-unit definition of an arbitrary number of instantiations.

The nice part, over C++, is that the generic instantiation is localized to a single translation-unit file, so you don't have to yell at the junior devs for instantiating templates without using an 'extern' construct.