OCaml library : Nativeint (original) (raw)
Module Nativeint
module Nativeint: sig
.. end
Processor-native integers.
This module provides operations on the type nativeint
of signed 32-bit integers (on 32-bit platforms) or signed 64-bit integers (on 64-bit platforms). This integer type has exactly the same width as that of a pointer type in the C compiler. All arithmetic operations overnativeint
are taken modulo 232 or 264 depending on the word size of the architecture.
Performance notice: values of type nativeint
occupy more memory space than values of type int
, and arithmetic operations onnativeint
are generally slower than those on int
. Use nativeint
only when the application requires the extra bit of precision over the int
type.
Literals for native integers are suffixed by n:
let zero: nativeint = 0n
let one: nativeint = 1n
let m_one: nativeint = -1n
val zero : nativeint
val one : nativeint
val minus_one : nativeint
val neg : nativeint -> nativeint
val add : nativeint -> nativeint -> nativeint
val sub : nativeint -> nativeint -> nativeint
val mul : nativeint -> nativeint -> nativeint
val div : nativeint -> nativeint -> nativeint
Integer division. This division rounds the real quotient of its arguments towards zero, as specified for (/).
- Raises
Division_by_zero
if the second argument is zero.
val unsigned_div : nativeint -> nativeint -> nativeint
Same as Nativeint.div, except that arguments and result are interpreted as unsigned native integers.
- Since 4.08
val rem : nativeint -> nativeint -> nativeint
Integer remainder. If y
is not zero, the result of Nativeint.rem x y
satisfies the following properties:Nativeint.zero <= Nativeint.rem x y < Nativeint.abs y
andx = Nativeint.add (Nativeint.mul (Nativeint.div x y) y) (Nativeint.rem x y)
. If y = 0
, Nativeint.rem x y
raises Division_by_zero
.
val unsigned_rem : nativeint -> nativeint -> nativeint
Same as Nativeint.rem, except that arguments and result are interpreted as unsigned native integers.
- Since 4.08
val succ : nativeint -> nativeint
Successor.Nativeint.succ x
is Nativeint.add x Nativeint.one
.
val pred : nativeint -> nativeint
Predecessor.Nativeint.pred x
is Nativeint.sub x Nativeint.one
.
val abs : nativeint -> nativeint
abs x
is the absolute value of x
. On min_int
this is min_int
itself and thus remains negative.
val size : int
The size in bits of a native integer. This is equal to 32
on a 32-bit platform and to 64
on a 64-bit platform.
val max_int : nativeint
The greatest representable native integer, either 231 - 1 on a 32-bit platform, or 263 - 1 on a 64-bit platform.
val min_int : nativeint
The smallest representable native integer, either -231 on a 32-bit platform, or -263 on a 64-bit platform.
val logand : nativeint -> nativeint -> nativeint
val logor : nativeint -> nativeint -> nativeint
val logxor : nativeint -> nativeint -> nativeint
Bitwise logical exclusive or.
val lognot : nativeint -> nativeint
Bitwise logical negation.
val shift_left : nativeint -> int -> nativeint
Nativeint.shift_left x y
shifts x
to the left by y
bits. The result is unspecified if y < 0
or y >= bitsize
, where bitsize
is 32
on a 32-bit platform and64
on a 64-bit platform.
val shift_right : nativeint -> int -> nativeint
Nativeint.shift_right x y
shifts x
to the right by y
bits. This is an arithmetic shift: the sign bit of x
is replicated and inserted in the vacated bits. The result is unspecified if y < 0
or y >= bitsize
.
val shift_right_logical : nativeint -> int -> nativeint
Nativeint.shift_right_logical x y
shifts x
to the right by y
bits. This is a logical shift: zeroes are inserted in the vacated bits regardless of the sign of x
. The result is unspecified if y < 0
or y >= bitsize
.
val of_int : int -> nativeint
Convert the given integer (type int
) to a native integer (type nativeint
).
val to_int : nativeint -> int
Convert the given native integer (type nativeint
) to an integer (type int
). The high-order bit is lost during the conversion.
val unsigned_to_int : nativeint -> int option
Same as Nativeint.to_int, but interprets the argument as an unsigned integer. Returns None
if the unsigned value of the argument cannot fit into anint
.
- Since 4.08
val of_float : float -> nativeint
Convert the given floating-point number to a native integer, discarding the fractional part (truncate towards 0). If the truncated floating-point number is outside the range [Nativeint.min_int, Nativeint.max_int], no exception is raised, and an unspecified, platform-dependent integer is returned.
val to_float : nativeint -> float
Convert the given native integer to a floating-point number.
val of_int32 : int32 -> nativeint
Convert the given 32-bit integer (type int32
) to a native integer.
val to_int32 : nativeint -> int32
Convert the given native integer to a 32-bit integer (type int32
). On 64-bit platforms, the 64-bit native integer is taken modulo 232, i.e. the top 32 bits are lost. On 32-bit platforms, the conversion is exact.
val of_string : string -> nativeint
Convert the given string to a native integer. The string is read in decimal (by default, or if the string begins with 0u
) or in hexadecimal, octal or binary if the string begins with 0x
, 0o
or 0b
respectively.
The 0u
prefix reads the input as an unsigned integer in the range[0, 2*Nativeint.max_int+1]
. If the input exceeds Nativeint.max_int it is converted to the signed integerInt64.min_int + input - Nativeint.max_int - 1
.
- Raises
Failure
if the given string is not a valid representation of an integer, or if the integer represented exceeds the range of integers representable in typenativeint
.
val of_string_opt : string -> nativeint option
Same as of_string
, but return None
instead of raising.
- Since 4.05
val to_string : nativeint -> string
Return the string representation of its argument, in decimal.
type ``t = nativeint
An alias for the type of native integers.
val compare : [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt) -> int
The comparison function for native integers, with the same specification ascompare. Along with the type t
, this function compare
allows the module Nativeint
to be passed as argument to the functorsSet.Make and Map.Make.
val unsigned_compare : [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt) -> int
Same as Nativeint.compare, except that arguments are interpreted as unsigned native integers.
- Since 4.08
val equal : [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt) -> bool
The equal function for native ints.
- Since 4.03
val min : [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt)
Return the smaller of the two arguments.
- Since 4.13
val max : [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt) -> [t](Nativeint.html#TYPEt)
Return the greater of the two arguments.
- Since 4.13
val seeded_hash : int -> [t](Nativeint.html#TYPEt) -> int
A seeded hash function for native ints, with the same output value asHashtbl.seeded_hash. This function allows this module to be passed as argument to the functor Hashtbl.MakeSeeded.
- Since 5.1
val hash : [t](Nativeint.html#TYPEt) -> int
An unseeded hash function for native ints, with the same output value asHashtbl.hash. This function allows this module to be passed as argument to the functor Hashtbl.Make.
- Since 5.1