# Module Int64

    module Int64: sig .. end

64-bit integers.

This module provides operations on the type `int64` of signed 64-bit integers. Unlike the built-in `int` type, the type `int64` is guaranteed to be exactly 64-bit wide on all platforms. All arithmetic operations over `int64` are taken modulo 264

Performance notice: values of type `int64` occupy more memory space than values of type `int`, and arithmetic operations on `int64` are generally slower than those on `int`. Use `int64` only when the application requires exact 64-bit arithmetic.

    val zero : int64

The 64-bit integer 0.

    val one : int64

The 64-bit integer 1.

    val minus_one : int64

The 64-bit integer -1.

    val neg : int64 -> int64

Unary negation.

    val add : int64 -> int64 -> int64

Addition.

    val sub : int64 -> int64 -> int64

Subtraction.

    val mul : int64 -> int64 -> int64

Multiplication.

    val div : int64 -> int64 -> int64

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 `(/)`.

    val rem : int64 -> int64 -> int64

Integer remainder. If `y` is not zero, the result of `Int64.rem x y` satisfies the following property: `x = Int64.add (Int64.mul (Int64.div x y) y) (Int64.rem x y)`. If `y = 0`, `Int64.rem x y` raises `Division_by_zero`.

    val succ : int64 -> int64

Successor. `Int64.succ x` is `Int64.add x Int64.one`.

    val pred : int64 -> int64

Predecessor. `Int64.pred x` is `Int64.sub x Int64.one`.

    val abs : int64 -> int64

Return the absolute value of its argument.

    val max_int : int64

The greatest representable 64-bit integer, 263 - 1.

    val min_int : int64

The smallest representable 64-bit integer, -263.

    val logand : int64 -> int64 -> int64

Bitwise logical and.

    val logor : int64 -> int64 -> int64

Bitwise logical or.

    val logxor : int64 -> int64 -> int64

Bitwise logical exclusive or.

    val lognot : int64 -> int64

Bitwise logical negation.

    val shift_left : int64 -> int -> int64

`Int64.shift_left x y` shifts `x` to the left by `y` bits. The result is unspecified if `y < 0` or `y >= 64`.

    val shift_right : int64 -> int -> int64

`Int64.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 >= 64`.

    val shift_right_logical : int64 -> int -> int64

`Int64.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 >= 64`.

    val of_int : int -> int64

Convert the given integer (type `int`) to a 64-bit integer (type `int64`).

    val to_int : int64 -> int

Convert the given 64-bit integer (type `int64`) to an integer (type `int`). On 64-bit platforms, the 64-bit integer is taken modulo 263, i.e. the high-order bit is lost during the conversion. On 32-bit platforms, the 64-bit integer is taken modulo 231, i.e. the top 33 bits are lost during the conversion.

    val of_float : float -> int64

Convert the given floating-point number to a 64-bit integer, discarding the fractional part (truncate towards 0). The result of the conversion is undefined if, after truncation, the number is outside the range [`Int64.min_int`, `Int64.max_int`].

    val to_float : int64 -> float

Convert the given 64-bit integer to a floating-point number.

    val of_int32 : int32 -> int64

Convert the given 32-bit integer (type `int32`) to a 64-bit integer (type `int64`).

    val to_int32 : int64 -> int32

Convert the given 64-bit integer (type `int64`) to a 32-bit integer (type `int32`). The 64-bit integer is taken modulo 232, i.e. the top 32 bits are lost during the conversion.

    val of_nativeint : nativeint -> int64

Convert the given native integer (type `nativeint`) to a 64-bit integer (type `int64`).

    val to_nativeint : int64 -> nativeint

Convert the given 64-bit integer (type `int64`) to a native integer. On 32-bit platforms, the 64-bit integer is taken modulo 232. On 64-bit platforms, the conversion is exact.

    val of_string : string -> int64

Convert the given string to a 64-bit 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*Int64.max_int+1]`. If the input exceeds `Int64.max_int` it is converted to the signed integer `Int64.min_int + input - Int64.max_int - 1`.

The `_` (underscore) character can appear anywhere in the string and is ignored. Raise `Failure "Int64.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 `int64`.

    val of_string_opt : string -> int64 option

Same as `of_string`, but return `None` instead of raising.

- Since 4.05

    val to_string : int64 -> string

Return the string representation of its argument, in decimal.

    val bits_of_float : float -> int64

Return the internal representation of the given float according to the IEEE 754 floating-point 'double format' bit layout. Bit 63 of the result represents the sign of the float; bits 62 to 52 represent the (biased) exponent; bits 51 to 0 represent the mantissa.

    val float_of_bits : int64 -> float

Return the floating-point number whose internal representation, according to the IEEE 754 floating-point 'double format' bit layout, is the given `int64`.

    type t = int64

An alias for the type of 64-bit integers.

    val compare : t -> t -> int

The comparison function for 64-bit integers, with the same specification as `compare`. Along with the type `t`, this function `compare` allows the module `Int64` to be passed as argument to the functors `Set.Make` and `Map.Make`.

    val equal : t -> t -> bool

The equal function for int64s.

- Since 4.03.0