Nativeint

Section: OCaml library (3)
Updated: 2009-07-27
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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 long integer 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.

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. Raise Division_by_zero if the second argument is zero. This division rounds the real quotient of its arguments towards zero, as specified for Pervasives.(/) .

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 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

Return the absolute value of its argument.

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 greatest 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 of_float : float -> nativeint

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 [ Nativeint.min_int , Nativeint.max_int ].

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 in hexadecimal, octal or binary if the string begins with 0x , 0o or 0b respectively. Raise 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 nativeint .

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 Pervasives.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 .