`type t` = `[`

`|` `Email_message.Email_selector.Base.t`
`|` ``envelope_sender of Re2.t`
`|` ``exists_envelope_recipient of Re2.t`
`|` ``all_envelope_recipients of Re2.t`

`]```
`include sig ... end`
`val t_of_sexp : Base.Sexp.t ‑> t`
`val __t_of_sexp__ : Base.Sexp.t ‑> t`
`val sexp_of_t : t ‑> Base.Sexp.t`
`val matches : t ‑> Async_smtp_types__.Envelope.t ‑> bool`
`val matches' : t ‑> Async_smtp_types__.Envelope_bodiless.t ‑> bool`