This module provides operations on the type nativeint of signed 32-bit integers (on 32-bit platforms) or signed 64-bit integers (on 64-bit platforms). This integer type has exactly the same width as that of a pointer type in the C compiler. All arithmetic operations over nativeint are taken modulo 232 or 264 depending on the word size of the architecture.
Performance notice: values of type nativeint occupy more memory space than values of type int, and arithmetic operations on nativeint are generally slower than those on int. Use nativeint only when the application requires the extra bit of precision over the int type.
Literals for native integers are suffixed by n:
let zero: nativeint = 0n
let one: nativeint = 1n
let m_one: nativeint = -1n
Same as div, except that arguments and result are interpreted as unsigned native integers.
since 4.08
Sourceval rem : nativeint ->nativeint -> nativeint
Integer remainder. If y is not zero, the result of Nativeint.rem x y satisfies the following properties: Nativeint.zero <= Nativeint.rem x y < Nativeint.abs y and x = Nativeint.add (Nativeint.mul (Nativeint.div x y) y) (Nativeint.rem x y). If y = 0, Nativeint.rem x y raises Division_by_zero.
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.
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.
Nativeint.shift_left x y shifts x to the left by y bits. The result is unspecified if y < 0 or y >= bitsize, where bitsize is 32 on a 32-bit platform and 64 on a 64-bit platform.
Nativeint.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 >= bitsize.
Nativeint.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 >= bitsize.
Convert the given floating-point number to a native integer, discarding the fractional part (truncate towards 0). If the truncated floating-point number is outside the range [Nativeint.min_int, Nativeint.max_int], no exception is raised, and an unspecified, platform-dependent integer is returned.
Convert the given native integer to a 32-bit integer (type int32). On 64-bit platforms, the 64-bit native integer is taken modulo 232, i.e. the top 32 bits are lost. On 32-bit platforms, the conversion is exact.
Convert the given string to a native 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*Nativeint.max_int+1]. If the input exceeds Nativeint.max_int it is converted to the signed integer Int64.min_int + input - Nativeint.max_int - 1.
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 nativeint.
The comparison function for native integers, with the same specification as Stdlib.compare. Along with the type t, this function compare allows the module Nativeint to be passed as argument to the functors Set.Make and Map.Make.
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.
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 size inclusive such that 0 <= n < 2{^i} (unsigned).
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 size inclusive such that -2{^i-1} <= n < 2{^i-1} (signed).
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 64 inclusive. If n is negative, leading_zeros n = 0 since the most significant bit of n is 1. leading_zeros n = size if and only if n = zero. Note that leading_zeros n + unsigned_bitsize n = size.
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 63 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 = size.
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 size inclusive. It is the largest integer i <= size such that 2{^i} divides n evenly. For example, trailing_zeros n = 0 if and only if n is odd, and trailing_zeros n = size if and only if n = zero.
A seeded hash function for native 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.
An unseeded hash function for native ints, with the same output value as Hashtbl.hash. This function allows this module to be passed as argument to the functor Hashtbl.Make.