A packed array is a read-only array that has a fairly compact representation and will not be traversed by the GC. It's designed for cases where you might construct a very large array once and then read from it many times. Array access is reasonably efficient. Be warned, however, that construction can be excruciatingly slow and might even perform many intermediate allocations, depending on the type of array.
module type Basic = sig .. end
Basic is the minimal interface you need to provide to make a packed array for a new type.
type elt
type t
val length : t -> int
val unsafe_get : t -> int -> elt
val of_array : elt array -> t
val unsafe_slice : t -> pos:int -> len:int -> t
val bin_elt : elt Core.Std.Bin_prot.Type_class.t
val bin_read_elt : elt Core.Std.Bin_prot.Read.reader
val __bin_read_elt__ : (int -> elt) Core.Std.Bin_prot.Read.reader
val bin_reader_elt : elt Core.Std.Bin_prot.Type_class.reader
val bin_size_elt : elt Core.Std.Bin_prot.Size.sizer
val bin_write_elt : elt Core.Std.Bin_prot.Write.writer
val bin_writer_elt : elt Core.Std.Bin_prot.Type_class.writer
val elt_of_sexp : Sexplib.Sexp.t -> elt
val sexp_of_elt : elt -> Sexplib.Sexp.t
module type S = sig .. end
S is the packed array interface.
include Basic
include Core.Std.Sexpable.S with type t := t
include Core.Std.Binable.S with type t := t
val get : t -> int -> elt
val slice : t -> pos:int -> len:int -> t
val iter : t -> f:(elt -> unit) -> unit
val fold : t -> init:'a -> f:('a -> elt -> 'a) -> 'a
val of_array : elt array -> t
val to_array : t -> elt array
val of_list : elt list -> t
val to_list : t -> elt list
val empty : t
module Make : 
functor (B : Basic) -> S with type t := B.t and type elt := B.elt
module Of_binable : 
functor (B : sig .. end) -> S with type elt := B.t
The representation of a packed array type created using Of_binable is a Bin_prot buffer and a packed array of indices pointing to the beginning of each serialized element in the buffer.
module Tuple2 : 
functor (A : Basic) ->
functor (B : Basic) -> sig .. end
the representation of a packed array of tuples is a tuple of packed arrays. This makes the zip_exn and unzip functions constant time.
type elt = A.elt * B.elt
include S with type elt := elt
val zip_exn : A.t -> B.t -> t
val unzip : t -> A.t * B.t
module Of_packed_array : 
functor (P : S) -> sig .. end
Of_packed_array(P) creates a packed array of packed arrays. The representation is a P.t and packed array of indices into it which point to the beginning of each inner array.
include S with type elt := P.t
val concat : t -> P.t
module Bool : S with type elt := bool
These primitive packed arrays are represented by their respective Bigarray types.
module Char : S with type elt := char
module Int : S with type elt := int
module Int8_unsigned : S with type elt := int
module Int8 : S with type elt := int
module Int16_unsigned : S with type elt := int
module Int16 : S with type elt := int
module Int32 : S with type elt := int32
module Int64 : S with type elt := int64
module Float32 : S with type elt := float
module Float : S with type elt := float
module String : S with type elt := string