https://github.com/encalmo/lens

Library for Scala > 3.6.2 providing Lens[R,V] typeclass derivation
https://github.com/encalmo/lens

lenses scala scala3 scala3-metaprogramming

Last synced: 3 months ago
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Library for Scala > 3.6.2 providing Lens[R,V] typeclass derivation

• Host: GitHub
• URL: https://github.com/encalmo/lens
• Owner: encalmo
• License: apache-2.0
• Created: 2025-01-06T13:48:16.000Z (6 months ago)
• Default Branch: main
• Last Pushed: 2025-03-18T16:27:39.000Z (3 months ago)
• Last Synced: 2025-03-18T16:41:12.244Z (3 months ago)
• Topics: lenses, scala, scala3, scala3-metaprogramming
• Language: Scala
• Homepage: https://encalmo.github.io/lens/
• Size: 31.3 KB
• Stars: 2
• Watchers: 0
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
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# lens

Scala library providing Lens[R,V] typeclass derivation.

## Dependencies

   - [Scala](https://www.scala-lang.org/) >= 3.6.2

## Usage

Use with SBT

    libraryDependencies += "org.encalmo" % "lens_3" % "0.9.0"

or with SCALA-CLI

    //> using dep org.encalmo::lens:0.9.2

## Examples

```scala

    case class Person(firstName: String, lastName: String, address: Address)

    case class Address(street1: String, street2: Option[String] = None, postcode: String, town: String, country: String)

    val townLens = Lens[Person].address.town

    

    val mike = Person("Mike","Hart", Address("1 Abbey Road", None, "BN15 KJ", "Exeter", "United Kingdom"))

    val town =  townLens.get(mike)

    townLens.set(mike)("Derby")

    townLens.update(mike, town => town.toUpperCase())

```