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Module Value

module Value: sig .. end
Arbitrary values (based on the Obj module)

This module builds upon the Obj module. It provides the Value.tag and Value.custom types to provide better dispatch on the internal type of any OCaml value. It also provides functions to inspect the representation of values, and to generate human-readable descriptions and mnemonics for use by the Dot and Sexpr module.


Types

type t = Obj.t
Value.t is the same as Obj.t
type tag =
| Lazy
| Closure
| Object
| Infix
| Forward
| Block
| Abstract
| String
| Double
| Double_array
| Custom
| Int
| Out_of_heap
| Unaligned
This allows better dispatch than comparing the tags.
type custom =
| Custom_nativeint of nativeint
| Custom_int32 of int32
| Custom_int64 of int64
| Custom_bigarray
| Custom_channel
| Custom_unknown
| Not_custom
Information about custom types
module TagSet: sig .. end
A set of tags

Hashtbl.HashedType

val equal : t -> t -> bool
Equality predicate (physical equality only!)
val hash : t -> int
Hashing function (used

Value representation

val bits : t -> nativeint
Return the raw bits of a value
val bits_to_string : ?base:[ `Bin | `Dec | `Hex ] -> t -> string
Return a string describing the low-level bit pattern of a value.
val tag : t -> tag
Tag type of a value
val heap_words : t -> int
Number of words that the value occupies on the heap (without the block header).
val is_in_heap : t -> bool
Int, Out_of_heap and Unaligned are out.

Custom Blocks

val custom_identifier : t -> string
Returns the identifier of the custom block
val custom_value : t -> custom
val custom_ops_info : t -> string
Info about the available operations (finalize / compare / hash / serialize / deserialize), which the custom block provides.

E.g. FCHSD, FC---, -----

val custom_is_int : t -> bool
Is the custom value a int32, int64 or nativeint?
val custom_has_finalize : t -> bool
Supports finalization?
val custom_has_compare : t -> bool
Supports comparison?
val custom_has_hash : t -> bool
Supports hashing?
val custom_has_serialize : t -> bool
Supports serialization?
val custom_has_deserialize : t -> bool
Supports deserialization?

Value Descriptions

val mnemonic : t -> string
Mnemonic or identifier for a value
val mnemonic_unknown : string
Mnemonic for an unknown/abstract value,
val abbrev : t -> string
Abbreviated, readable description of a value
val description : t -> string
Readable description of a value