Monocle is a pure functional, optics library for Scala providing immutable data access and transformation tools — including Lens, Prism, Iso, Optional, and Traversal. It enables composable, declarative modifications of deeply nested immutable structures in a concise and type-safe fashion.

Features

  • Core optics: Lens, Prism, Iso, Optional, Traversal
  • Safe, immutable access/modification without boilerplate
  • Composable optics chains using composeLens, composeTraversal
  • Integration with Cats, Cats Effect, and typeclass-based workflows
  • Support for Scala 2 and 3, and multiple data structures (case classes, ADTs)
  • Compatible with Scala.js and Scala Native

Project Samples

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License

MIT License

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Additional Project Details

Programming Language

Scala

Related Categories

Scala Libraries

Registered

2025-08-04