19.13 
Module Int64: 64bit integers 

This module provides operations on the type int64
of
signed 64bit integers. Unlike the builtin int
type,
the type int64
is guaranteed to be exactly 64bit wide on all
platforms. All arithmetic operations over int64
are taken
modulo 2^{64}.
The type int64
is supported on all 64bit platforms, as well as
on all 32bit platforms for which the C compiler supports 64bit
arithmetic. On 32bit platforms without support for 64bit arithmetic,
all functions in this module raise an Invalid_argument
exception.
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 64bit arithmetic.
val zero : int64
val one : int64
val minus_one : int64
The 64bit integers 0, 1, 1.
val neg : int64 > int64
Unary negation.
val add : int64 > int64 > int64
Addition.
val sub : int64 > int64 > int64
Subtraction.
val mul : int64 > int64 > int64
Multiplication.
val div : int64 > int64 > int64
Integer division. Raise Division_by_zero
if the second
argument is zero.
val rem : int64 > int64 > int64
Integer remainder. If x >= 0
and y > 0
, the result
of Int64.rem x y
satisfies the following properties:
0 <= Int64.rem x y < y
and
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
.
If x < 0
or y < 0
, the result of Int64.rem x y
is
not specified and depends on the platform.
val succ : int64 > int64
Successor. Int64.succ x
is Int64.add x Int64.one
.
val pred : int64 > int64
Predecessor. Int64.pred x
is Int64.sub x Int64.one
.
val abs : int64 > int64
Return the absolute value of its argument.
val max_int : int64
The greatest representable 64bit integer, 2^{63}  1.
val min_int : int64
The smallest representable 64bit integer, 2^{63}.
val logand : int64 > int64 > int64
Bitwise logical and.
val logor : int64 > int64 > int64
Bitwise logical or.
val logxor : int64 > int64 > int64
Bitwise logical exclusive or.
val lognot : int64 > int64
Bitwise logical negation
val shift_left : int64 > int > int64
Int64.shift_left x y
shifts x
to the left by y
bits.
The result is unspecified if y < 0
or y >= 64
.
val shift_right : int64 > int > int64
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
.
val shift_right_logical : int64 > int > int64
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
.
val of_int : int > int64
Convert the given integer (type int
) to a 64bit integer
(type int64
).
val to_int : int64 > int
Convert the given 64bit integer (type int64
) to an
integer (type int
). On 64bit platforms, the 64bit integer
is taken modulo 2^{63}, i.e. the highorder bit is lost
during the conversion. On 32bit platforms, the 64bit integer
is taken modulo 2^{31}, i.e. the top 33 bits are lost
during the conversion.
val of_float : float > int64
Convert the given floatingpoint number to a 64bit 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
.
val to_float : int64 > float
Convert the given 64bit integer to a floatingpoint number.
val of_int32 : int32 > int64
Convert the given 32bit integer (type int32
)
to a 64bit integer (type int64
).
val to_int32 : int64 > int32
Convert the given 64bit integer (type int64
) to a
32bit integer (type int32
). The 64bit integer
is taken modulo 2^{32}, i.e. the top 32 bits are lost
during the conversion.
val of_nativeint : nativeint > int64
Convert the given native integer (type nativeint
)
to a 64bit integer (type int64
).
val to_nativeint : int64 > nativeint
Convert the given 64bit integer (type int64
) to a
native integer. On 32bit platforms, the 64bit integer
is taken modulo 2^{32}. On 64bit platforms,
the conversion is exact.
val of_string : string > int64
Convert the given string to a 64bit 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.
val to_string : int64 > string
Return the string representation of its argument, in decimal.
val format : string > int64 > string
Int64.format fmt n
return the string representation of the
64bit integer n
in the format specified by fmt
.
fmt
is a Printf
style format containing exactly
one 0
, 0
, 0
, 0
, 0
or 0
conversion specification.
See the documentation of the Printf
module for more information,
val bits_of_float : float > int64
Return the internal representation of the given float according
to the IEEE 754 floatingpoint ``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.
val float_of_bits : int64 > float
Return the floatingpoint number whose internal representation,
according to the IEEE 754 floatingpoint ``double format'' bit layout,
is the given int64
.