.TH "Nativeint" 3o source: 2019-01-25 OCamldoc "OCaml library"
.SH NAME
Nativeint \- Processor-native integers.
.SH Module
Module   Nativeint
.SH Documentation
.sp
Module
.BI "Nativeint"
 : 
.B sig  end

.sp
Processor\-native integers\&.
.sp
This module provides operations on the type 
.B 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
.B nativeint
are taken modulo 2^{32 or 2^{64 depending
on the word size of the architecture\&.
.sp
Performance notice: values of type 
.B nativeint
occupy more memory
space than values of type 
.B int
, and arithmetic operations on
.B nativeint
are generally slower than those on 
.B int
\&.  Use 
.B nativeint
only when the application requires the extra bit of precision
over the 
.B int
type\&.

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.sp
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.I val zero 
: 
.B nativeint
.sp
The native integer 0\&.

.sp

.I val one 
: 
.B nativeint
.sp
The native integer 1\&.

.sp

.I val minus_one 
: 
.B nativeint
.sp
The native integer \-1\&.

.sp

.I val neg 
: 
.B nativeint -> nativeint
.sp
Unary negation\&.

.sp

.I val add 
: 
.B nativeint -> nativeint -> nativeint
.sp
Addition\&.

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.I val sub 
: 
.B nativeint -> nativeint -> nativeint
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Subtraction\&.

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.I val mul 
: 
.B nativeint -> nativeint -> nativeint
.sp
Multiplication\&.

.sp

.I val div 
: 
.B nativeint -> nativeint -> nativeint
.sp
Integer division\&.  Raise 
.B Division_by_zero
if the second
argument is zero\&.  This division rounds the real quotient of
its arguments towards zero, as specified for 
.B Pervasives\&.(/)
\&.

.sp

.I val rem 
: 
.B nativeint -> nativeint -> nativeint
.sp
Integer remainder\&.  If 
.B y
is not zero, the result
of 
.B Nativeint\&.rem x y
satisfies the following properties:
.B Nativeint\&.zero <= Nativeint\&.rem x y < Nativeint\&.abs y
and
.B x = Nativeint\&.add (Nativeint\&.mul (Nativeint\&.div x y) y)
.B                       (Nativeint\&.rem x y)
\&.
If 
.B y = 0
, 
.B Nativeint\&.rem x y
raises 
.B Division_by_zero
\&.

.sp

.I val succ 
: 
.B nativeint -> nativeint
.sp
Successor\&.
.B Nativeint\&.succ x
is 
.B Nativeint\&.add x Nativeint\&.one
\&.

.sp

.I val pred 
: 
.B nativeint -> nativeint
.sp
Predecessor\&.
.B Nativeint\&.pred x
is 
.B Nativeint\&.sub x Nativeint\&.one
\&.

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.I val abs 
: 
.B nativeint -> nativeint
.sp
Return the absolute value of its argument\&.

.sp

.I val size 
: 
.B int
.sp
The size in bits of a native integer\&.  This is equal to 
.B 32
on a 32\-bit platform and to 
.B 64
on a 64\-bit platform\&.

.sp

.I val max_int 
: 
.B nativeint
.sp
The greatest representable native integer,
either 2^{31 \- 1 on a 32\-bit platform,
or 2^{63 \- 1 on a 64\-bit platform\&.

.sp

.I val min_int 
: 
.B nativeint
.sp
The smallest representable native integer,
either \-2^{31 on a 32\-bit platform,
or \-2^{63 on a 64\-bit platform\&.

.sp

.I val logand 
: 
.B nativeint -> nativeint -> nativeint
.sp
Bitwise logical and\&.

.sp

.I val logor 
: 
.B nativeint -> nativeint -> nativeint
.sp
Bitwise logical or\&.

.sp

.I val logxor 
: 
.B nativeint -> nativeint -> nativeint
.sp
Bitwise logical exclusive or\&.

.sp

.I val lognot 
: 
.B nativeint -> nativeint
.sp
Bitwise logical negation

.sp

.I val shift_left 
: 
.B nativeint -> int -> nativeint
.sp

.B Nativeint\&.shift_left x y
shifts 
.B x
to the left by 
.B y
bits\&.
The result is unspecified if 
.B y < 0
or 
.B y >= bitsize
,
where 
.B bitsize
is 
.B 32
on a 32\-bit platform and
.B 64
on a 64\-bit platform\&.

.sp

.I val shift_right 
: 
.B nativeint -> int -> nativeint
.sp

.B Nativeint\&.shift_right x y
shifts 
.B x
to the right by 
.B y
bits\&.
This is an arithmetic shift: the sign bit of 
.B x
is replicated
and inserted in the vacated bits\&.
The result is unspecified if 
.B y < 0
or 
.B y >= bitsize
\&.

.sp

.I val shift_right_logical 
: 
.B nativeint -> int -> nativeint
.sp

.B Nativeint\&.shift_right_logical x y
shifts 
.B x
to the right
by 
.B y
bits\&.
This is a logical shift: zeroes are inserted in the vacated bits
regardless of the sign of 
.B x
\&.
The result is unspecified if 
.B y < 0
or 
.B y >= bitsize
\&.

.sp

.I val of_int 
: 
.B int -> nativeint
.sp
Convert the given integer (type 
.B int
) to a native integer
(type 
.B nativeint
)\&.

.sp

.I val to_int 
: 
.B nativeint -> int
.sp
Convert the given native integer (type 
.B nativeint
) to an
integer (type 
.B int
)\&.  The high\-order bit is lost during
the conversion\&.

.sp

.I val of_float 
: 
.B float -> nativeint
.sp
Convert the given floating\-point number to a native integer,
discarding the fractional part (truncate towards 0)\&.
The result of the conversion is undefined if, after truncation,
the number is outside the range
[
.B Nativeint\&.min_int
, 
.B Nativeint\&.max_int
]\&.

.sp

.I val to_float 
: 
.B nativeint -> float
.sp
Convert the given native integer to a floating\-point number\&.

.sp

.I val of_int32 
: 
.B int32 -> nativeint
.sp
Convert the given 32\-bit integer (type 
.B int32
)
to a native integer\&.

.sp

.I val to_int32 
: 
.B nativeint -> int32
.sp
Convert the given native integer to a
32\-bit integer (type 
.B 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\&.

.sp

.I val of_string 
: 
.B string -> nativeint
.sp
Convert the given string to a native integer\&.
The string is read in decimal (by default) or in hexadecimal,
octal or binary if the string begins with 
.B 0x
, 
.B 0o
or 
.B 0b
respectively\&.
Raise 
.B Failure "int_of_string"
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 
.B nativeint
\&.

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.I val of_string_opt 
: 
.B string -> nativeint option
.sp
Same as 
.B of_string
, but return 
.B None
instead of raising\&.

.sp
.B "Since"
4.05

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.I val to_string 
: 
.B nativeint -> string
.sp
Return the string representation of its argument, in decimal\&.

.sp
.I type t 
= 
.B nativeint

.sp
An alias for the type of native integers\&.

.sp

.I val compare 
: 
.B t -> t -> int
.sp
The comparison function for native integers, with the same specification as
.B Pervasives\&.compare
\&.  Along with the type 
.B t
, this function 
.B compare
allows the module 
.B Nativeint
to be passed as argument to the functors
.B Set\&.Make
and 
.B Map\&.Make
\&.

.sp

.I val equal 
: 
.B t -> t -> bool
.sp
The equal function for native ints\&.

.sp
.B "Since"
4.03.0

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