never_returns
should be used as the return type of functions that don't return and
might block forever, rather than 'a
or _
. This forces callers of such functions
to have a call to never_returns
at the call site, which makes it clear to readers
what's going on. We do not intend to use this type for functions such as failwithf
that always raise an exception.
val sexp_of_never_returns : never_returns ‑> Sexplib.Sexp.t
val never_returns : Core_kernel.Nothing.t ‑> 'a