Macro pub_impl_methods 

macro_rules! pub_impl_methods {
    { $(
    fn $name:ident $( [ $($generics:tt)* ] )? (
        ,
        $( $param:ident: $ptype:ty ),*
    ) -> $ret:ty;
)* } => { ... };
}

Define ordinary methods in impl .. for DynTimeProvider

This macro exists mostly to avoid copypaste mistakes where we (for example) implement block_advance by calling release_advance.