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Module Nativeint

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 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.

Literals for native integers are suffixed by n:

     let zero: nativeint = 0n
     let one: nativeint = 1n
     let m_one: nativeint = -1n
    
let zero: nativeint;

The native integer 0.

let one: nativeint;

The native integer 1.

let minus_one: nativeint;

The native integer -1.

let neg: nativeint => nativeint;

Unary negation.

let add: (nativeint, nativeint) => nativeint;

Addition.

let sub: (nativeint, nativeint) => nativeint;

Subtraction.

let mul: (nativeint, nativeint) => nativeint;

Multiplication.

let div: (nativeint, nativeint) => nativeint;

Integer division. This division rounds the real quotient of its arguments towards zero, as specified for (/).

let unsigned_div: (nativeint, nativeint) => nativeint;

Same as Nativeint.div, except that arguments and result are interpreted as unsigned native integers.

let 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.

let unsigned_rem: (nativeint, nativeint) => nativeint;

Same as Nativeint.rem, except that arguments and result are interpreted as unsigned native integers.

let succ: nativeint => nativeint;

Successor. Nativeint.succ x is Nativeint.add x Nativeint.one.

let pred: nativeint => nativeint;

Predecessor. Nativeint.pred x is Nativeint.sub x Nativeint.one.

let abs: nativeint => nativeint;

Return the absolute value of its argument.

let 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.

let max_int: nativeint;

The greatest representable native integer, either 231 - 1 on a 32-bit platform, or 263 - 1 on a 64-bit platform.

let min_int: nativeint;

The smallest representable native integer, either -231 on a 32-bit platform, or -263 on a 64-bit platform.

let logand: (nativeint, nativeint) => nativeint;

Bitwise logical and.

let logor: (nativeint, nativeint) => nativeint;

Bitwise logical or.

let logxor: (nativeint, nativeint) => nativeint;

Bitwise logical exclusive or.

let lognot: nativeint => nativeint;

Bitwise logical negation.

let 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.

let 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.

let 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.

let of_int: int => nativeint;

Convert the given integer (type int) to a native integer (type nativeint).

let 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.

let unsigned_to_int: nativeint => option(int);

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.

let 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].

let to_float: nativeint => float;

Convert the given native integer to a floating-point number.

let of_int32: int32 => nativeint;

Convert the given 32-bit integer (type int32) to a native integer.

let 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 232, i.e. the top 32 bits are lost. On 32-bit platforms, the conversion is exact.

let 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.

let of_string_opt: string => option(nativeint);

Same as of_string, but return None instead of raising.

let to_string: nativeint => string;

Return the string representation of its argument, in decimal.

type t = nativeint;

An alias for the type of native integers.

let 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.

let unsigned_compare: (t, t) => int;

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

let equal: (t, t) => bool;

The equal function for native ints.