Nativeint(3) | OCaml library | Nativeint(3) |

# NAME

Nativeint - Processor-native integers.

# Module

Module Nativeint

# Documentation

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 over
**nativeint** are taken modulo 2^32 or 2^64 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 on
**nativeint** 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**

The native integer 0.

*val one* : **nativeint**

The native integer 1.

*val minus_one* : **nativeint**

The native integer -1.

*val neg* : **nativeint -> nativeint**

Unary negation.

*val add* : **nativeint -> nativeint ->
nativeint**

Addition.

*val sub* : **nativeint -> nativeint ->
nativeint**

Subtraction.

*val mul* : **nativeint -> nativeint ->
nativeint**

Multiplication.

*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** and **x
= 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 2^31 - 1 on a 32-bit platform, or 2^63 - 1 on a 64-bit platform.

*val min_int* : **nativeint**

The smallest representable native integer, either -2^31 on a 32-bit platform, or -2^63 on a 64-bit platform.

*val logand* : **nativeint -> nativeint ->
nativeint**

Bitwise logical and.

*val logor* : **nativeint -> nativeint ->
nativeint**

Bitwise logical or.

*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 and
**64** 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 an **int** .

**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 2^32, 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 integer
**Int64.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 type **nativeint** .

*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 -> t -> int**

The comparison function for native integers, with the same
specification as **compare** . Along with the type **t** , this
function **compare** allows the module **Nativeint** to be passed as
argument to the functors **Set.Make** and **Map.Make** .

*val unsigned_compare* : **t -> t -> int**

Same as **Nativeint.compare** , except that arguments are
interpreted as unsigned native integers.

**Since** 4.08

*val equal* : **t -> t -> bool**

The equal function for native ints.

**Since** 4.03

*val min* : **t -> t -> t**

Return the smaller of the two arguments.

**Since** 4.13

*val max* : **t -> t -> t**

Return the greater of the two arguments.

**Since** 4.13

*val seeded_hash* : **int -> t -> int**

A seeded hash function for native ints, with the same output value
as **Hashtbl.seeded_hash** . This function allows this module to be
passed as argument to the functor **Hashtbl.MakeSeeded** .

**Since** 5.1

*val hash* : **t -> int**

An unseeded hash function for native ints, with the same output
value as **Hashtbl.hash** . This function allows this module to be passed
as argument to the functor **Hashtbl.Make** .

**Since** 5.1

2023-11-11 | OCamldoc |