.TH "Nativeint" 3o 2023-09-18 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 
.ft B
nativeint
.ft R
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
.ft B
nativeint
.ft R
are taken modulo 2^32 or 2^64 depending
on the word size of the architecture\&.
.sp
Performance notice: values of type 
.ft B
nativeint
.ft R
occupy more memory
space than values of type 
.ft B
int
.ft R
, and arithmetic operations on
.ft B
nativeint
.ft R
are generally slower than those on 
.ft B
int
.ft R
\&.  Use 
.ft B
nativeint
.ft R
only when the application requires the extra bit of precision
over the 
.ft B
int
.ft R
type\&.
.sp
Literals for native integers are suffixed by n:
.EX
.ft B
.br
\&     let zero: nativeint = 0n
.br
\&     let one: nativeint = 1n
.br
\&     let m_one: nativeint = \-1n
.br
\&    
.ft R
.EE

.sp

.sp
.sp

.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\&.

.sp

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

.sp

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

.sp

.I val div 
: 
.B nativeint -> nativeint -> nativeint
.sp
Integer division\&. This division rounds the real quotient of
its arguments towards zero, as specified for 
.ft B
(/)
.ft R
\&.

.sp
.B "Raises Division_by_zero"
if the second
argument is zero\&.

.sp

.I val unsigned_div 
: 
.B nativeint -> nativeint -> nativeint
.sp
Same as 
.ft B
Nativeint\&.div
.ft R
, except that arguments and result are interpreted as     unsigned native integers\&.

.sp
.B "Since"
4.08.0

.sp

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

.sp

.I val unsigned_rem 
: 
.B nativeint -> nativeint -> nativeint
.sp
Same as 
.ft B
Nativeint\&.rem
.ft R
, except that arguments and result are interpreted as     unsigned native integers\&.

.sp
.B "Since"
4.08.0

.sp

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

.sp

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

.sp

.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 
.ft B
32
.ft R
on a 32\-bit platform and to 
.ft B
64
.ft R
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

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

.sp

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

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

.sp

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

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

.sp

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

.sp

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

.sp

.I val unsigned_to_int 
: 
.B nativeint -> int option
.sp
Same as 
.ft B
Nativeint\&.to_int
.ft R
, but interprets the argument as an unsigned integer\&.
Returns 
.ft B
None
.ft R
if the unsigned value of the argument cannot fit into an
.ft B
int
.ft R
\&.

.sp
.B "Since"
4.08.0

.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)\&.
If the truncated floating\-point number is outside the range
[
.ft B
Nativeint\&.min_int
.ft R
, 
.ft B
Nativeint\&.max_int
.ft R
], no exception is raised,
and an unspecified, platform\-dependent integer is returned\&.

.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 
.ft B
int32
.ft R
)
to a native integer\&.

.sp

.I val to_int32 
: 
.B nativeint -> int32
.sp
Convert the given native integer to a
32\-bit integer (type 
.ft B
int32
.ft R
)\&.  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 if the string
begins with 
.ft B
0u
.ft R
) or in hexadecimal, octal or binary if the
string begins with 
.ft B
0x
.ft R
, 
.ft B
0o
.ft R
or 
.ft B
0b
.ft R
respectively\&.
.sp
The 
.ft B
0u
.ft R
prefix reads the input as an unsigned integer in the range
.ft B
[0, 2*Nativeint\&.max_int+1]
.ft R
\&.  If the input exceeds 
.ft B
Nativeint\&.max_int
.ft R
it is converted to the signed integer
.ft B
Int64\&.min_int + input \- Nativeint\&.max_int \- 1
.ft R
\&.

.sp
.B "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 
.ft B
nativeint
.ft R
\&.

.sp

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

.sp
.B "Since"
4.05

.sp

.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
.ft B
compare
.ft R
\&.  Along with the type 
.ft B
t
.ft R
, this function 
.ft B
compare
.ft R
allows the module 
.ft B
Nativeint
.ft R
to be passed as argument to the functors
.ft B
Set\&.Make
.ft R
and 
.ft B
Map\&.Make
.ft R
\&.

.sp

.I val unsigned_compare 
: 
.B t -> t -> int
.sp
Same as 
.ft B
Nativeint\&.compare
.ft R
, except that arguments are interpreted as unsigned
native integers\&.

.sp
.B "Since"
4.08.0

.sp

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

.sp
.B "Since"
4.03.0

.sp

.I val min 
: 
.B t -> t -> t
.sp
Return the smaller of the two arguments\&.

.sp
.B "Since"
4.13.0

.sp

.I val max 
: 
.B t -> t -> t
.sp
Return the greater of the two arguments\&.

.sp
.B "Since"
4.13.0

.sp