How to use the state< S, R... > metarule.

[tylercecil]

I'm having trouble understanding the state metarule, and there aren't currently any examples that use it (please correct me if I'm wrong, and point me to the example). Just some basic questions:

• What constructors must be available for my state type?
• What should the signature of success() be?
  I think a small example would really help me out, if possible.

[d-frey]

You can have a look at the Switching-Style documentation page, there we also mention pegtl/contrib/raw_string.hh as an example.

In the example, you can also find the basic signature for both the constructor as well as the success() method:

template< typename Input, typename ... States >
raw_string_state( const Input &, States && ... )
{ }

template< typename Input, typename ... States >
void success( const Input &, States && ... ) const
{ }

This applies if you want to basically ignore all the (outer) states (which might as well be no states). In most cases, however, you want to apply the collected data of your state class to the outer state.

Is this sufficient? (We might want to extend the example-section in the future anyways, but don't hold your breath)

[tylercecil]

Thanks @d-frey, that's really all that I needed! More examples in the future might be helpful, but for now I think I'll be ok.