# package ocaml-base-compiler

64-bit integers.

This module provides operations on the type `int64`

of signed 64-bit integers. Unlike the built-in `int`

type, the type `int64`

is guaranteed to be exactly 64-bit wide on all platforms. All arithmetic operations over `int64`

are taken modulo 2^{64}

Performance notice: values of type `int64`

occupy more memory space than values of type `int`

, and arithmetic operations on `int64`

are generally slower than those on `int`

. Use `int64`

only when the application requires exact 64-bit arithmetic.

Literals for 64-bit integers are suffixed by L:

```
let zero: int64 = 0L
let one: int64 = 1L
let m_one: int64 = -1L
```

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.(/)`

.

Same as `div`

, except that arguments and result are interpreted as *unsigned* 64-bit integers.

Integer remainder. If `y`

is not zero, the result of `Int64.rem x y`

satisfies the following property: `x = Int64.add (Int64.mul (Int64.div x y) y) (Int64.rem x y)`

. If `y = 0`

, `Int64.rem x y`

raises `Division_by_zero`

.

Same as `rem`

, except that arguments and result are interpreted as *unsigned* 64-bit integers.

`Int64.shift_left x y`

shifts `x`

to the left by `y`

bits. The result is unspecified if `y < 0`

or `y >= 64`

.

`Int64.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 >= 64`

.

`Int64.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 >= 64`

.

Convert the given 64-bit integer (type `int64`

) to an integer (type `int`

). On 64-bit platforms, the 64-bit integer is taken modulo 2^{63}, i.e. the high-order bit is lost during the conversion. On 32-bit platforms, the 64-bit integer is taken modulo 2^{31}, i.e. the top 33 bits are lost during the conversion.

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`

.

Convert the given floating-point number to a 64-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 [`Int64.min_int`

, `Int64.max_int`

].

Convert the given 32-bit integer (type `int32`

) to a 64-bit integer (type `int64`

).

Convert the given 64-bit integer (type `int64`

) to a 32-bit integer (type `int32`

). The 64-bit integer is taken modulo 2^{32}, i.e. the top 32 bits are lost during the conversion.

Convert the given native integer (type `nativeint`

) to a 64-bit integer (type `int64`

).

Convert the given 64-bit integer (type `int64`

) to a native integer. On 32-bit platforms, the 64-bit integer is taken modulo 2^{32}. On 64-bit platforms, the conversion is exact.

Convert the given string to a 64-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*Int64.max_int+1]`

. If the input exceeds `Int64.max_int`

it is converted to the signed integer `Int64.min_int + input - Int64.max_int - 1`

.

The `_`

(underscore) character can appear anywhere in the string and is ignored. Raise `Failure "Int64.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 `int64`

.

Return the internal representation of the given float according to the IEEE 754 floating-point 'double format' bit layout. Bit 63 of the result represents the sign of the float; bits 62 to 52 represent the (biased) exponent; bits 51 to 0 represent the mantissa.

Return the floating-point number whose internal representation, according to the IEEE 754 floating-point 'double format' bit layout, is the given `int64`

.

The comparison function for 64-bit integers, with the same specification as `Stdlib.compare`

. Along with the type `t`

, this function `compare`

allows the module `Int64`

to be passed as argument to the functors `Set.Make`

and `Map.Make`

.

Same as `compare`

, except that arguments are interpreted as *unsigned* 64-bit integers.