Operations on internal representations of values.
Not for the casual user.
val repr : 'a -> t
val obj : t -> 'a
val is_block : t -> bool
val is_int : t -> bool
val tag : t -> int
val size : t -> int
val 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 excluded.
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_tag. However, for
set_tag, in the case of immutable blocks where the middle-end optimizers never see code that discriminates on their tag (for example records), the operation should be safe. Such uses are nonetheless discouraged.
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 set_tag : t -> int -> unit
val double_field : t -> int -> float
val set_double_field : t -> int -> float -> unit
val new_block : int -> int -> t
val truncate : t -> int -> unit
The following two functions are deprecated. Use module
val marshal : t -> bytes
- deprecated Use Marshal.to_bytes instead.
val unmarshal : bytes -> int -> t * int
- deprecated Use Marshal.from_bytes and Marshal.total_size instead.
module Ephemeron : sig ... end
Ephemeron with arbitrary arity and untyped