Module Stdlib.Obj

Operations on internal representations of values.

Not for the casual user.

type t

type t;

type raw_data = nativeint

type raw_data = nativeint;

val repr : 'a -> t

let repr: 'a => t;

val obj : t -> 'a

let obj: t => 'a;

val magic : 'a -> 'b

let magic: 'a => 'b;

val is_block : t -> bool

let is_block: t => bool;

val is_int : t -> bool

let is_int: t => bool;

val tag : t -> int

let tag: t => int;

val size : t -> int

let size: t => int;

val reachable_words : t -> int

let reachable_words: t => int;

Computes the total size (in words, including the headers) of all heap blocks accessible from the argument. Statically allocated blocks are included.

since 4.04

val field : t -> int -> t

let field: t => int => t;

val set_field : t -> int -> t -> unit

let set_field: t => int => t => unit;

When using flambda:

set_field MUST NOT be called on immutable blocks. (Blocks allocated in C stubs, or with new_block below, are always considered mutable.)

The same goes for set_double_field.

For experts only: set_field et al can be made safe by first wrapping the block in Sys.opaque_identity, so any information about its contents will not be propagated.

val double_field : t -> int -> float

let double_field: t => int => float;

val set_double_field : t -> int -> float -> unit

let set_double_field: t => int => float => unit;

val raw_field : t -> int -> raw_data

let raw_field: t => int => raw_data;

val set_raw_field : t -> int -> raw_data -> unit

let set_raw_field: t => int => raw_data => unit;

val new_block : int -> int -> t

let new_block: int => int => t;

val dup : t -> t

let dup: t => t;

val add_offset : t -> Int32.t -> t

let add_offset: t => Int32.t => t;

val with_tag : int -> t -> t

let with_tag: int => t => t;

val first_non_constant_constructor_tag : int

let first_non_constant_constructor_tag: int;

val last_non_constant_constructor_tag : int

let last_non_constant_constructor_tag: int;

val forcing_tag : int

let forcing_tag: int;

val cont_tag : int

let cont_tag: int;

val lazy_tag : int

let lazy_tag: int;

val closure_tag : int

let closure_tag: int;

val object_tag : int

let object_tag: int;

val infix_tag : int

let infix_tag: int;

val forward_tag : int

let forward_tag: int;

val no_scan_tag : int

let no_scan_tag: int;

val abstract_tag : int

let abstract_tag: int;

val string_tag : int

let string_tag: int;

val double_tag : int

let double_tag: int;

val double_array_tag : int

let double_array_tag: int;

val custom_tag : int

let custom_tag: int;

val int_tag : int

let int_tag: int;

val out_of_heap_tag : int

let out_of_heap_tag: int;

val unaligned_tag : int

let unaligned_tag: int;

module Extension_constructor : sig ... end

module Extension_constructor: { ... };

module Ephemeron : sig ... end

module Ephemeron: { ... };

Ephemeron with arbitrary arity and untyped