Stdlib.Int32(3)

💖 Stdlib.Int32 💖

okay so this is the Stdlib.Int32 page from the OCaml library — section 3 of the manual, bestie, and it's literally all about our fave little 32-bit integer module. it's giving "small but mighty" ✨

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✨ NAME ✨

Stdlib.Int32 — the manpage itself says "no description" 😭 which is so unhelpful of it, but dw, the whole rest of the page is the description fr fr 💅

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🎀 Module 🎀

Module Stdlib.Int32

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💅 Documentation 💅

Module Int32 : (module Stdlib__Int32)

okay now the good stuff 👑

🧊 the constants

val zero : int32

The 32-bit integer 0. that's it. that's the whole vibe 🫶

val one : int32

The 32-bit integer 1. iconic, no notes 💅

val minus_one : int32

The 32-bit integer -1. the og hater 🙈

➕ arithmetic era

val neg : int32 -> int32

Unary negation. flip the sign, slay ✨

val add : int32 -> int32 -> int32

Addition. math is mathing 💖

val sub : int32 -> int32 -> int32

Subtraction. bye bye numbers 🌸

val mul : int32 -> int32 -> int32

Multiplication. it's giving growth 🔥

val div : int32 -> int32 -> int32

Integer division. this one rounds the real quotient of its arguments towards zero, exactly as specified for (/) 💅

Raises Division_by_zero if the second argument is zero. bestie. do NOT divide by zero, i'm begging 😭

val unsigned_div : int32 -> int32 -> int32

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

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. so basically don't do that 🙈

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

🧮 the division girlies (floor / ceil / euclidean)

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. so precise, so demure 💅

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. the ceiling to fdiv's floor, we love a duo 🫶

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. mathematically blessed ✨

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. so this one never gets moody 🌸

Since 5.5

Raises Division_by_zero if the second argument is 0.

🐾 stepping

val succ : int32 -> int32

Successor. Int32.succ x is Int32.add x Int32.one. one lil step forward 🦋

val pred : int32 -> int32

Predecessor. Int32.pred x is Int32.sub x Int32.one. one lil step back 💜

val abs : int32 -> int32

abs x is the absolute value of x. On min_int this is min_int itself and thus remains negative. ⚠️ yeah that's a real caveat, the edge case is lowkey cursed but that's just how it is 💀

🚧 the boundaries

val max_int : int32

The greatest representable 32-bit integer, 2^31 - 1. the ceiling fr fr 👑

val min_int : int32

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

🔢 bitwise behaviour

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.

🌀 shifting

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. unspecified means don't come crying to me, bestie 😭

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.

🔄 conversions

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. so it wraps, okay? 🎀

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. platform-dependent behaviour, we stay unbothered 💅

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. no exception, just a polite None 🫶

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. like. it just returns some guy 😭💀

val to_float : int32 -> float

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

📝 strings

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. so many prefixes, so many vibes ✨

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. so 1_000 is fine, aesthetic 🎀

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. the chill version 😌

Since 4.05

val to_string : int32 -> string

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

🧚 float bits shenanigans

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. bit archaeology 🔍

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.

👑 the type + comparisons

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. functor-ready, we love to see it 💅

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

🧬 bit nerds corner

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. counting the ones, obsessed 🧮

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. math checks out ✨

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

#️⃣ hashing

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

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and that's the whole page bestie, no cap 💜 this lil doc was brought to you by OCamldoc, dated 2026-06-22, straight out of the OCaml library section 3 manual — go forth and 32-bit integer responsibly 🫶✨🎀