Module Stdlib.Int32

32-bit integers.

This module provides operations on the type int32 of signed 32-bit integers. Unlike the built-in int type, the type int32 is guaranteed to be exactly 32-bit wide on all platforms. All arithmetic operations over int32 are taken modulo 232.

Performance notice: values of type int32 occupy more memory space than values of type int, and arithmetic operations on int32 are generally slower than those on int. Use int32 only when the application requires exact 32-bit arithmetic.

Literals for 32-bit integers are suffixed by l:

let zero: int32 = 0l
let one: int32 = 1l
let m_one: int32 = -1l
let zero: int32;

The 32-bit integer 0.

let one: int32;

The 32-bit integer 1.

let minus_one: int32;

The 32-bit integer -1.

let neg: int32 => int32;

Unary negation.

let add: int32 => int32 => int32;

Addition.

let sub: int32 => int32 => int32;

Subtraction.

let mul: int32 => int32 => int32;

Multiplication.

let div: int32 => int32 => int32;

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

let unsigned_div: int32 => int32 => int32;

Same as div, except that arguments and result are interpreted as unsigned 32-bit integers.

  • since 4.08
let rem: int32 => int32 => int32;

Integer remainder. If y is not zero, the result of Int32.rem x y satisfies the following property: x = Int32.add (Int32.mul (Int32.div x y) y) (Int32.rem x y). If y = 0, Int32.rem x y raises Division_by_zero.

let unsigned_rem: int32 => int32 => int32;

Same as rem, except that arguments and result are interpreted as unsigned 32-bit integers.

  • since 4.08
let succ: int32 => int32;

Successor. Int32.succ x is Int32.add x Int32.one.

let pred: int32 => int32;

Predecessor. Int32.pred x is Int32.sub x Int32.one.

let abs: int32 => int32;

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

let max_int: int32;

The greatest representable 32-bit integer, 231 - 1.

let min_int: int32;

The smallest representable 32-bit integer, -231.

let logand: int32 => int32 => int32;

Bitwise logical and.

let logor: int32 => int32 => int32;

Bitwise logical or.

let logxor: int32 => int32 => int32;

Bitwise logical exclusive or.

let lognot: int32 => int32;

Bitwise logical negation.

let shift_left: int32 => int => int32;

Int32.shift_left x y shifts x to the left by y bits. The result is unspecified if y < 0 or y >= 32.

let shift_right: int32 => int => int32;

Int32.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 >= 32.

let shift_right_logical: int32 => int => int32;

Int32.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 >= 32.

let of_int: int => int32;

Convert the given integer (type int) to a 32-bit integer (type int32). On 64-bit platforms, the argument is taken modulo 232.

let to_int: int32 => int;

Convert the given 32-bit integer (type int32) to an integer (type int). On 32-bit platforms, the 32-bit integer is taken modulo 231, i.e. the high-order bit is lost during the conversion. On 64-bit platforms, the conversion is exact.

let unsigned_to_int: int32 => 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
let of_float: float => int32;

Convert the given floating-point number to a 32-bit integer, discarding the fractional part (truncate towards 0). If the truncated floating-point number is outside the range [Int32.min_int, Int32.max_int], no exception is raised, and an unspecified, platform-dependent integer is returned.

let to_float: int32 => float;

Convert the given 32-bit integer to a floating-point number.

let of_string: string => int32;

Convert the given string to a 32-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*Int32.max_int+1]. If the input exceeds Int32.max_int it is converted to the signed integer Int32.min_int + input - Int32.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 int32.

let of_string_opt: string => option(int32);

Same as of_string, but return None instead of raising.

  • since 4.05
let to_string: int32 => string;

Return the string representation of its argument, in signed decimal.

let bits_of_float: float => int32;

Return the internal representation of the given float according to the IEEE 754 floating-point 'single format' bit layout. Bit 31 of the result represents the sign of the float; bits 30 to 23 represent the (biased) exponent; bits 22 to 0 represent the mantissa.

let float_of_bits: int32 => float;

Return the floating-point number whose internal representation, according to the IEEE 754 floating-point 'single format' bit layout, is the given int32.

type t = int32;

An alias for the type of 32-bit integers.

let compare: t => t => int;

The comparison function for 32-bit integers, with the same specification as Stdlib.compare. Along with the type t, this function compare allows the module Int32 to be passed as argument to the functors Set.Make and Map.Make.

let unsigned_compare: t => t => int;

Same as compare, except that arguments are interpreted as unsigned 32-bit integers.

  • since 4.08
let equal: t => t => bool;

The equal function for int32s.

  • since 4.03
let min: t => t => t;

Return the smaller of the two arguments.

  • since 4.13
let max: t => t => t;

Return the greater of the two arguments.

  • since 4.13
let seeded_hash: int => t => int;

A seeded hash function for 32-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
let hash: t => int;

An unseeded hash function for 32-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