[](http://www.crossroadlabs.xyz/)
# Regex
[](https://raw.githubusercontent.com/crossroadlabs/Regex/master/LICENSE)
[](https://travis-ci.org/crossroadlabs/Regex)
[](https://github.com/crossroadlabs/Regex/releases)
[](https://github.com/Carthage/Carthage)
[](https://cocoapods.org/pods/CrossroadRegex)
## Advanced regular expressions for Swift
## Goals
[
](https://github.com/crossroadlabs/Express) Regex library was mainly introduced to fulfill the needs of [Swift Express](https://github.com/crossroadlabs/Express) - web application server side framework for Swift.
Still we hope it will be useful for everybody else.
[Happy regexing ;)](#examples)
## Features
- [x] Deep Integration with Swift
- [x] `=~` operator support
- [x] Swift Pattern Matching (aka `switch` operator) support
- [x] Named groups
- [x] Match checking
- [x] Extraction/Search functions
- [x] Replace functions
- [x] With a pattern
- [x] With custom replacing function
- [x] Splitting with a Regular Expression
- [x] Simple
- [x] With groups
- [x] String extensions
- [x] Supports grapheme clusters 👨👩👧
## Extra
Path to Regex converter is available as a separate library here: [PathToRegex](https://github.com/crossroadlabs/PathToRegex)
This one allows using path patterns like `/folder/*/:file.txt` or `/route/:one/:two` to be converted to Regular Expressions and matched against strings.
## Getting started
### Installation
#### [Package Manager](https://swift.org/package-manager/)
Add the following dependency to your [Package.swift](https://github.com/apple/swift-package-manager/blob/master/Documentation/Usage.md#define-dependencies):
```swift
.Package(url: "https://github.com/crossroadlabs/Regex.git", majorVersion: 1)
```
Run ```swift build``` and build your app.
#### [CocoaPods](http://cocoapods.org/)
Add the following to your [Podfile](http://guides.cocoapods.org/using/the-podfile.html):
```rb
pod 'CrossroadRegex'
```
Make sure that you are integrating your dependencies using frameworks: add `use_frameworks!` to your Podfile. Then run `pod install`.
#### [Carthage](https://github.com/Carthage/Carthage)
Add the following to your [Cartfile](https://github.com/Carthage/Carthage/blob/master/Documentation/Artifacts.md#cartfile):
```
github "crossroadlabs/Regex"
```
Run `carthage update` and follow the steps as described in Carthage's [README](https://github.com/Carthage/Carthage#adding-frameworks-to-an-application).
#### Manually
1. Download and drop ```/Regex``` folder in your project.
2. Congratulations!
### Examples
#### Hello Regex:
All the lines below are identical and represent simple matching. All operators and `matches` function return Bool
```swift
//operator way, can match either regex or string containing pattern
"l321321alala" =~ "(.+?)([123]*)(.*)".r
"l321321alala" =~ "(.+?)([123]*)(.*)"
//similar function
"(.+?)([123]*)(.*)".r!.matches("l321321alala")
```
Operator `!~` returns `true` if expression does **NOT** match:
```swift
"l321321alala" !~ "(.+?)([123]*)(.*)".r
"l321321alala" !~ "(.+?)([123]*)(.*)"
//both return false
```
#### Swift Pattern Matching (aka `switch` keyword)
Regex provides very deep integration with Swift and can be used with the switch keyword in the following way:
```swift
let letter = "a"
let digit = "1"
let other = "!"
//you just put your string is a regular Swift's switch to match to regular expressions
switch letter {
//note .r after the string literal of the pattern
case "\\d".r: print("digit")
case "[a-z]".r: print("letter")
default: print("bizarre symbol")
}
switch digit {
case "\\d".r: print("digit")
case "[a-z]".r: print("letter")
default: print("bizarre symbol")
}
switch other {
//note .r after the string literal of the pattern
case "\\d".r: print("digit")
case "[a-z]".r: print("letter")
default: print("bizarre symbol")
}
```
The output of the code above will be:
```
letter
digit
bizarre symbol
```
#### Accessing groups:
```swift
// strings can be converted to regex in Scala style .r property of a string
let digits = "(.+?)([123]*)(.*)".r?.findFirst(in: "l321321alala")?.group(at: 2)
// digits is "321321" here
```
#### Named groups:
```swift
let regex:RegexType = try Regex(pattern:"(.+?)([123]*)(.*)",
groupNames:"letter", "digits", "rest")
let match = regex.findFirst(in: "l321321alala")
if let match = match {
let letter = match.group(named: "letter")
let digits = match.group(named: "digits")
let rest = match.group(named: "rest")
//do something with extracted data
}
```
#### Replace:
```swift
let replaced = "(.+?)([123]*)(.*)".r?.replaceAll(in: "l321321alala", with: "$1-$2-$3")
//replaced is "l-321321-alala"
```
#### Replace with custom replacer function:
```swift
let replaced = "(.+?)([123]+)(.+?)".r?.replaceAll(in: "l321321la321a") { match in
if match.group(at: 1) == "l" {
return nil
} else {
return match.matched.uppercaseString
}
}
//replaced is "l321321lA321A"
```
#### Split:
In the following example, split() looks for 0 or more spaces followed by a semicolon followed by 0 or more spaces and, when found, removes the spaces from the string. nameList is the array returned as a result of split().
```swift
let names = "Harry Trump ;Fred Barney; Helen Rigby ; Bill Abel ;Chris Hand"
let nameList = names.split(using: "\\s*;\\s*".r)
//name list contains ["Harry Trump", "Fred Barney", "Helen Rigby", "Bill Abel", "Chris Hand"]
```
#### Split with groups:
If separator contains capturing parentheses, matched results are returned in the array.
```swift
let myString = "Hello 1 word. Sentence number 2."
let splits = myString.split(using: "(\\d)".r)
//splits contains ["Hello ", "1", " word. Sentence number ", "2", "."]
```
## Changelog
You can view the [CHANGELOG](./CHANGELOG.md) as a separate document [here](./CHANGELOG.md).
## Contributing
To get started, sign the Contributor License Agreement.
## [ by Crossroad Labs](http://www.crossroadlabs.xyz/)