swift-int2x

Create Double-Width Integers with Ease

Synopsis

import Int2X

typealias U128 = UInt2X<UInt64> // Yes.  That's it!
typealias I128 = Int2X<UInt64>  // ditto for signed integers

Description

Thanks to SE-0104, making your own integer types is easier than ever. This module makes use of it -- creating double-width integer from any given FixedWidthInteger.

U?Int{128,256,512,1024} are predefined as follows:

public typealias UInt128    = UInt2X<UInt64>
public typealias UInt256    = UInt2X<UInt128>
public typealias UInt512    = UInt2X<UInt256>
public typealias UInt1024   = UInt2X<UInt512>

public typealias Int128    = Int2X<UInt64>
public typealias Int256    = Int2X<UInt128>
public typealias Int512    = Int2X<UInt256>
public typealias Int1024   = Int2X<UInt512>

As you see, UInt2X and Int2X themselves are FixedWidthInteger so you can stack them up.

Usage

build

$ git clone https://github.com/dankogai/swift-int2x.git
$ cd swift-int2x # the following assumes your $PWD is here
$ swift build

REPL

$ scripts/run-repl.sh

$ swift run --repl

and in your repl,

Welcome to Apple Swift version 4.2 (swiftlang-1000.11.37.1 clang-1000.11.45.1). Type :help for assistance.
  1> import Int2X 
  2> Int1024.max.description
$R0: String = "89884656743115795386465259539451236680898848947115328636715040578866337902750481566354238661203768010560056939935696678829394884407208311246423715319737062188883946712432742638151109800623047059726541476042502884419075341171231440736956555270413618581675255342293149119973622969239858152417678164812112068607"

From Your SwiftPM-Managed Projects

Add the following to the dependencies section:

.package(
  url: "https://github.com/dankogai/swift-int2x.git", .branch("main")
)

and the following to the .target argument:

.target(
  name: "YourSwiftyPackage",
  dependencies: ["Int2X"])

Now all you have to do is:

import Int2X

in your code. Enjoy!

Prerequisite

Swift 5 or better, OS X or Linux to build.