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5.15  Module Nativeint

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 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 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 : 'a nativeint
The native integer 0.

val one : 'a nativeint
The native integer 1.

val minus_one : 'a nativeint
The native integer -1.

val neg : 'a nativeint -> 'a nativeint
Unary negation.

val add : 'a nativeint -> 'a nativeint -> 'a nativeint

val sub : 'a nativeint -> 'a nativeint -> 'a nativeint

val mul : 'a nativeint -> 'a nativeint -> 'a nativeint

val div : 'a nativeint ->
          'b nativeint -{'c | Division_by_zero: 'c |}-> 'a nativeint
          with 'b < 'a, 'c
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 : 'a nativeint ->
          'b nativeint -{'c | Division_by_zero: 'c |}-> 'a nativeint
          with 'b < 'a, 'c
Integer remainder.

val succ : 'a nativeint -> 'a nativeint
Successor. Nativeint.succ x is Nativeint.add x

val pred : 'a nativeint -> 'a nativeint
Predecessor. Nativeint.pred x is Nativeint.sub x

val abs : 'a nativeint -> 'a nativeint
Return the absolute value of its argument.

val size : 'a 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 : 'a 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 : 'a nativeint
The greatest representable native integer, either -231 on a 32-bit platform, or -263 on a 64-bit platform.

val logand : 'a nativeint -> 'a nativeint -> 'a nativeint
Bitwise logical and.

val logor : 'a nativeint -> 'a nativeint -> 'a nativeint
Bitwise logical or.

val logxor : 'a nativeint -> 'a nativeint -> 'a nativeint
Bitwise logical exclusive or.

val lognot : 'a nativeint -> 'a nativeint
Bitwise logical negation

val shift_left : 'a nativeint -> 'a int -> 'a 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 : 'a nativeint -> 'a int -> 'a 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 : 'a nativeint -> 'a int -> 'a 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 : 'a int -> 'a nativeint
Convert the given integer (type int) to a native integer (type nativeint).

val to_int : 'a nativeint -> 'a 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 : 'a float -> 'a 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 : 'a nativeint -> 'a float
Convert the given native integer to a floating-point number.

val of_int32 : 'a int32 -> 'a nativeint
Convert the given 32-bit integer (type int32) to a native integer.

val to_int32 : 'a nativeint -> 'a 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 : 'a string -{'b | Failure: 'b |}-> 'a nativeint
                with 'a < 'b
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.

val to_string : 'a nativeint -> 'a string
Return the string representation of its argument, in decimal.

type (#'a:level) t = 'a nativeint
An alias for the type of native integers.

val compare : 'a t -> 'a t -> 'a int
The comparison function for native integers, with the same specification as 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.

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