Nint128, as the name suggests, is a package to work with integers, signed and unsigned, of 128 bits.

Currently the package implements 128-bit operations in pure Nim. Therefore, it is highly portable.

For optimizations, you can use, when possible, the C extension for 128-bit integers present in the GCC and CLANG compiler or VCC compiler intrinsics. For more information, see this here.

Status

The basic implementation is ready, but not fully tested. Visit the tests directory to see what has been tested and what remains to be tested.

Some things may change and break down in the future.

Install

nimble install nint128

or

nimble install https://github.com/rockcavera/nim-nint128.git

Basic Use

import pkg/nint128

const
  u999 = u128("0b1111100111") ## Defines a constant from a binary string.
  uHigh = u128("0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF") ## Defines a constant from a hexadecimal string.
  i333 = i128("0b101001101") ## Defines a constant from a binary string.
  iHigh = i128("0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF") ## Defines a constant from a hexadecimal string.

## Comparisons `UInt128`
echo uHigh == high(UInt128)
echo uHigh != low(UInt128)
echo uHigh > zero(UInt128)
echo uHigh >= one(UInt128)
echo uHigh < ten(UInt128)
echo uHigh <= u999

## Comparisons `Int128`
echo iHigh == high(Int128)
echo iHigh != low(Int128)
echo iHigh > zero(Int128)
echo iHigh >= one(Int128)
echo iHigh < ten(Int128)
echo iHigh <= i333
echo isNegative(iHigh)

## Initialization of `UInt128` and `Int128` variables.
var
  a, b: UInt128
  c, d: Int128

a = u128(1234567890) ## Transforms the `int` `1234567890` into `UInt128`
b = u128("18446744073709551616") ## Transforms `string` `18446744073709551616` into `UInt128`

c = i128(1234567890) ## Transforms the `int` `-13579` into `Int128`
d = i128("-18446744073709551616") ## Transforms `string` `-18446744073709551616` to `Int128`

## Basic arithmetic `UInt128`
a = a + b
b = b - u128(9223372036854775808'u64)
a = a * u999
b = uHigh div a
b = uHigh mod a
(a, b) = divmod(uHigh, a)

## Basic arithmetic `Int128`
c = c + d
d = d - i333
c = c * i128("-3")
d = iHigh div c
d = iHigh mod c
(c, d) = divmod(iHigh, c)

## Bitwise operation `UInt128`
a = a and b
a = a or b
a = a xor b
a = not(a)
a = a shl 12
b = b shr 64

## Bitwise operation `Int128`
c = c and d
c = c or d
c = c xor d
c = not(c)
c = c shl 12
d = d shr 64

Documentation

https://rockcavera.github.io/nim-nint128/theindex.html

License

• The file div2n1n.nim, in the directory src/nint128/vendor/stint/, is authored by Status Research & Development GmbH, part of the stint package.
• The file endians2.nim, in the directory src/nint128/vendor/stew/, is authored by Status Research & Development GmbH, part of the stew package.