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

val zero : int32: The 32-bit integer 0.

val one : int32: The 32-bit integer 1.

val minus_one : int32: The 32-bit integer -1.

val neg : int32 -> int32: Unary negation.

val add : int32 -> int32 -> int32: Addition.

val sub : int32 -> int32 -> int32: Subtraction.

val mul : int32 -> int32 -> int32: Multiplication.

val div : int32 -> int32 -> int32: 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 Stdlib.(/).

val unsigned_div : int32 -> int32 -> int32

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

since: 4.08.0

val 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.

val unsigned_rem : int32 -> int32 -> int32

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

since: 4.08.0

val succ : int32 -> int32: Successor. Int32.succ x is Int32.add x Int32.one.

val pred : int32 -> int32: Predecessor. Int32.pred x is Int32.sub x Int32.one.

val abs : int32 -> int32: Return the absolute value of its argument.

val max_int : int32: The greatest representable 32-bit integer, 2³¹ - 1.

val min_int : int32: The smallest representable 32-bit integer, -2³¹.

val logand : int32 -> int32 -> int32: Bitwise logical and.

val logor : int32 -> int32 -> int32: Bitwise logical or.

val logxor : int32 -> int32 -> int32: Bitwise logical exclusive or.

val lognot : int32 -> int32: Bitwise logical negation.

val 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.

val 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.

val 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.

val 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.

val 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.

val unsigned_to_int : int32 -> 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: 4.08.0

val of_float : float -> int32: Convert the given floating-point number to a 32-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 [Int32.min_int, Int32.max_int].

val to_float : int32 -> float: Convert the given 32-bit integer to a floating-point number.

val 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. Raise Failure "Int32.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 int32.

val of_string_opt : string -> int32 option

Same as of_string, but return None instead of raising.

since: 4.05

val to_string : int32 -> string: Return the string representation of its argument, in signed decimal.

val 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.

val 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.

val 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.

val unsigned_compare : t -> t -> int

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

since: 4.08.0

val equal : t -> t -> bool

The equal function for int32s.

since: 4.03.0