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.

`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 `(/)`

.`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 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, 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`

).`val to_int : ``int32 -> int`

Convert the given 32-bit integer (type ^{31}, i.e. the high-order bit is lost
during the conversion. On 64-bit platforms, the conversion
is exact.

`int32`

) to an
integer (type `int`

). On 32-bit platforms, the 32-bit integer
is taken modulo 2`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 in hexadecimal,
octal or binary if the string begins with

`0x`

, `0o`

or `0b`

respectively.
Raise `Failure "int_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 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 equal : ``t -> t -> bool`

The equal function for int32s.

**Since** 4.03.0