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Module Stdlib.Int64

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.

Literals for 64-bit integers are suffixed by L:

ocaml
  let zero: int64 = 0L
  let one: int64 = 1L
  let m_one: int64 = -1L
reasonml
let zero: int64 = 0L;
let one: int64 = 1L;
let m_one: int64 = (-1L);
ocaml
val zero : int64
reasonml
let zero: int64;

The 64-bit integer 0.

ocaml
val one : int64
reasonml
let one: int64;

The 64-bit integer 1.

ocaml
val minus_one : int64
reasonml
let minus_one: int64;

The 64-bit integer -1.

ocaml
val neg : int64 -> int64
reasonml
let neg: int64 => int64;

Unary negation.

ocaml
val add : int64 -> int64 -> int64
reasonml
let add: int64 => int64 => int64;

Addition.

ocaml
val sub : int64 -> int64 -> int64
reasonml
let sub: int64 => int64 => int64;

Subtraction.

ocaml
val mul : int64 -> int64 -> int64
reasonml
let mul: int64 => int64 => int64;

Multiplication.

ocaml
val div : int64 -> int64 -> int64
reasonml
let div: int64 => int64 => int64;

Integer division.

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

ocaml
val unsigned_div : int64 -> int64 -> int64
reasonml
let unsigned_div: int64 => int64 => int64;

Same as div, except that arguments and result are interpreted as unsigned 64-bit integers.

since 4.08

ocaml
val rem : int64 -> int64 -> int64
reasonml
let 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.

ocaml
val unsigned_rem : int64 -> int64 -> int64
reasonml
let unsigned_rem: int64 => int64 => int64;

Same as rem, except that arguments and result are interpreted as unsigned 64-bit integers.

since 4.08

ocaml
val succ : int64 -> int64
reasonml
let succ: int64 => int64;

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

ocaml
val pred : int64 -> int64
reasonml
let pred: int64 => int64;

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

ocaml
val abs : int64 -> int64
reasonml
let abs: int64 => int64;

abs x is the absolute value of x. On min_int this is min_int itself and thus remains negative.

ocaml
val max_int : int64
reasonml
let max_int: int64;

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

ocaml
val min_int : int64
reasonml
let min_int: int64;

The smallest representable 64-bit integer, -263.

ocaml
val logand : int64 -> int64 -> int64
reasonml
let logand: int64 => int64 => int64;

Bitwise logical and.

ocaml
val logor : int64 -> int64 -> int64
reasonml
let logor: int64 => int64 => int64;

Bitwise logical or.

ocaml
val logxor : int64 -> int64 -> int64
reasonml
let logxor: int64 => int64 => int64;

Bitwise logical exclusive or.

ocaml
val lognot : int64 -> int64
reasonml
let lognot: int64 => int64;

Bitwise logical negation.

ocaml
val shift_left : int64 -> int -> int64
reasonml
let 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.

ocaml
val shift_right : int64 -> int -> int64
reasonml
let 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.

ocaml
val shift_right_logical : int64 -> int -> int64
reasonml
let 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.

ocaml
val of_int : int -> int64
reasonml
let of_int: int => int64;

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

ocaml
val to_int : int64 -> int
reasonml
let 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.

ocaml
val unsigned_to_int : int64 -> int option
reasonml
let unsigned_to_int: int64 => option(int);

Same as to_int, but interprets the argument as an unsigned integer. Returns None if the unsigned value of the argument cannot fit into an int.

since 4.08

ocaml
val of_float : float -> int64
reasonml
let of_float: float => int64;

Convert the given floating-point number to a 64-bit integer, discarding the fractional part (truncate towards 0). If the truncated floating-point number is outside the range [Int64.min_int, Int64.max_int], no exception is raised, and an unspecified, platform-dependent integer is returned.

ocaml
val to_float : int64 -> float
reasonml
let to_float: int64 => float;

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

ocaml
val of_int32 : int32 -> int64
reasonml
let of_int32: int32 => int64;

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

ocaml
val to_int32 : int64 -> int32
reasonml
let 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.

ocaml
val of_nativeint : nativeint -> int64
reasonml
let of_nativeint: nativeint => int64;

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

ocaml
val to_nativeint : int64 -> nativeint
reasonml
let 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.

ocaml
val of_string : string -> int64
reasonml
let 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.

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 int64.

ocaml
val of_string_opt : string -> int64 option
reasonml
let of_string_opt: string => option(int64);

Same as of_string, but return None instead of raising.

since 4.05

ocaml
val to_string : int64 -> string
reasonml
let to_string: int64 => string;

Return the string representation of its argument, in decimal.

ocaml
val bits_of_float : float -> int64
reasonml
let 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.

ocaml
val float_of_bits : int64 -> float
reasonml
let 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.

ocaml
type t = int64
reasonml
type t = int64;

An alias for the type of 64-bit integers.

ocaml
val compare : t -> t -> int
reasonml
let compare: t => t => int;

The comparison function for 64-bit integers, with the same specification as Stdlib.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.

ocaml
val unsigned_compare : t -> t -> int
reasonml
let unsigned_compare: t => t => int;

Same as compare, except that arguments are interpreted as unsigned 64-bit integers.

since 4.08

ocaml
val equal : t -> t -> bool
reasonml
let equal: t => t => bool;

The equal function for int64s.

since 4.03

ocaml
val min : t -> t -> t
reasonml
let min: t => t => t;

Return the smaller of the two arguments.

since 4.13

ocaml
val max : t -> t -> t
reasonml
let max: t => t => t;

Return the greater of the two arguments.

since 4.13

ocaml
val seeded_hash : int -> t -> int
reasonml
let seeded_hash: int => t => int;

A seeded hash function for 64-bit ints, with the same output value as Hashtbl.seeded_hash. This function allows this module to be passed as argument to the functor Hashtbl.MakeSeeded.

since 5.1

ocaml
val hash : t -> int
reasonml
let hash: t => int;

An unseeded hash function for 64-bit ints, with the same output value as Hashtbl.hash. This function allows this module to be passed as argument to the functor Hashtbl.Make.

since 5.1