'a t is a type that uses Core_kernel.am_running_test to determine if it should use the 'a sexp serializer, or serialize the type as '<hidden_in_test>'. It can be thought of as a form of @sexp.opaque that is conditional upon if tests are running.
include Bin_prot.Binable.S1 with type 'a t := 'a t
val bin_shape_t : Bin_prot.Shape.t -> Bin_prot.Shape.tval bin_size_t : ('a, 'a t) Bin_prot.Size.sizer1val bin_write_t : ('a, 'a t) Bin_prot.Write.writer1val bin_read_t : ('a, 'a t) Bin_prot.Read.reader1val __bin_read_t__ : ('a, int -> 'a t) Bin_prot.Read.reader1val bin_writer_t : ('a, 'a t) Bin_prot.Type_class.S1.writerval bin_reader_t : ('a, 'a t) Bin_prot.Type_class.S1.readerval bin_t : ('a, 'a t) Bin_prot.Type_class.S1.tval sexp_of_t : ('a -> Ppx_sexp_conv_lib.Sexp.t) -> 'a t -> Ppx_sexp_conv_lib.Sexp.tmodule With_non_roundtripping_in_test_of_sexp : sig ... endThis type also derives sexp. This will not allow you to roundtrip values you create in tests and should be used carefully.