zio / zio-prelude Edit

A lightweight, distinctly Scala take on functional abstractions, with tight ZIO integration

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ZIO Prelude

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ZIO Prelude is an alternative approach to functional abstractions in Scala, which throws out the classic functor hierarchy in favor of a modular algebraic approach that is smaller, easier to understand and teach, and more expressive.

ZIO Prelude has three key areas of focus:

  • Data structures, and type classes for traversing them. ZIO Prelude embraces the collections in the Scala standard library, and extends them with new instances and new useful additions.
  • Patterns of composition for types. ZIO Prelude provides a small catalog of patterns for binary operators, which combine two values into another value of the same type. These patterns are named after the algebraic laws they satisfy: associativity, commutativity, and identity.
  • Patterns of composition for type constructors. ZIO Prelude provides a catalog of patterns for binary operators on type constructors (things like Future, Option, ZIO Task). These patterns are named after the algebraic laws they satisfy (associativity, commutativity, and identity) and the structure they produce, whether a tuple or an either.

The library has a small research-stage package (zio.prelude.fx) that provides abstraction over expressive effect types like ZIO and ZPure.


Learn more on the ZIO Prelude Microsite!


Documentation for contributors

Code of Conduct

See the Code of Conduct


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