NAME

Int32 - 32-bit integers.

Module

Module Int32

Documentation

Module Int32
: sig end

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 2^32.

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

Raises Division_by_zero if the second argument is zero.

val unsigned_div : int32 -> int32 -> int32

Same as Int32.div , except that arguments and result are interpreted as unsigned 32-bit integers.

Since 4.08

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 Int32.rem , except that arguments and result are interpreted as unsigned 32-bit integers.

Since 4.08

val fdiv : int32 -> int32 -> int32

Floor division. fdiv x y is the real quotient x / y rounded down to an integer. We have fdiv x y <= div x y <= cdiv x y and cdiv x y - fdiv x y <= 1 .

Since 5.5

Raises Division_by_zero if the second argument is 0.

val cdiv : int32 -> int32 -> int32

Ceil division. cdiv x y is the real quotient x / y rounded up to an integer. We have fdiv x y <= div x y <= cdiv x y and cdiv x y - fdiv x y <= 1 .

Since 5.5

Raises Division_by_zero if the second argument is 0.

val ediv : int32 -> int32 -> int32

Euclidean division. ediv x y is the real quotient x / y rounded down to an integer if y > 0 and rounded up to an integer if y < 0 . The remainder erem x y = x - ediv x y * y is always non-negative. Moreover, ediv x (-y) = - ediv x y .

Since 5.5

Raises Division_by_zero if the second argument is 0.

val erem : int32 -> int32 -> int32

Euclidean remainder. If y is not zero, we have x = ediv x y * y + erem x y and 0 <= erem x y <= abs y - 1 . The result of erem x y is always non-negative, unlike the result of rem x y , which has the sign of x .

Since 5.5

Raises Division_by_zero if the second argument is 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

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

val max_int : int32

The greatest representable 32-bit integer, 2^31 - 1.

val min_int : int32

The smallest representable 32-bit integer, -2^31.

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 2^32.

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 2^31, 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 Int32.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 -> 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.

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.

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 .

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 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 Int32.compare , except that arguments are interpreted as unsigned 32-bit integers.

Since 4.08

val equal : t -> t -> bool

The equal function for int32s.

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 popcount : t -> int

Population count, also known as Hamming weight. popcount n is the number of 1 bits in the binary representation of n . Negative n are represented in two's complement.

Since 5.5

val unsigned_bitsize : t -> int

unsigned_bitsize n is the minimal number of bits needed to represent n as an unsigned binary number. It is the smallest integer i between 0 and 32 inclusive such that 0 <= n < 2{^i} (unsigned).

Since 5.5

val signed_bitsize : t -> int

signed_bitsize n is the minimal number of bits needed to represent n as a signed, two's complement binary number. It is the smallest integer i between 1 and 32 inclusive such that -2{^i-1} <= n < 2{^i-1} (signed).

Since 5.5

val leading_zeros : t -> int

leading_zeros n is the number of leading (most significant) 0 bits in the binary representation of n . It is an integer between 0 and 32 inclusive. If n is negative, leading_zeros n = 0 since the most significant bit of n is 1. leading_zeros n = 32 if and only if n = zero . Note that leading_zeros n + unsigned_bitsize n = 32 .

Since 5.5

val leading_sign_bits : t -> int

leading_sign_bits n is the number of leading (most significant) sign bits in the binary representation of n , excluding the sign bit itself. It is an integer between 0 and 31 inclusive. For positive n , it is the number of leading zero bits minus one. For negative n , it is the number of leading one bits minus one. Note that leading_sign_bits n + signed_bitsize n = 32 .

Since 5.5

val trailing_zeros : t -> int

trailing_zeros n is the number of trailing (least significant) 0 bits in the binary representation of n . It is an integer between 0 and 32 inclusive. It is the largest integer i <= 32 such that 2{^i} divides n evenly. For example, trailing_zeros n = 0 if and only if n is odd, and trailing_zeros n = 32 if and only if n = zero .

Since 5.5

val 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

val 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