package octez-proto-libs
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 264
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 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
.
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 263, i.e. the high-order bit is lost during the conversion. On 32-bit platforms, the 64-bit integer is taken modulo 231, i.e. the top 33 bits are lost during the conversion.
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 232, i.e. the top 32 bits are lost during the conversion.
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
.