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:

let zero: int64 = 0L
let one: int64 = 1L
let m_one: int64 = -1L
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.

  • 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.(/).

val unsigned_div : int64 -> int64 -> int64

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

  • since 4.08
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 unsigned_rem : int64 -> int64 -> int64

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

  • since 4.08
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

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

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 unsigned_to_int : int64 -> int option

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
val 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.

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.

  • 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.

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 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.

val unsigned_compare : t -> t -> int

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

  • since 4.08
val equal : t -> t -> bool

The equal function for int64s.

  • since 4.03
val min : t -> t -> t

Return the smaller of the two arguments.

  • since 4.13
val max : t -> t -> t

Return the greater of the two arguments.

  • since 4.13
val 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
val 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