Provides functions to restrict the arity of JavaScript functions. ES2015 makes this largely unnecessary, see the migration guide if you're using these.

First-order contracts for JavaScript. No replacement exists yet, but higher-order contracts are in the roadmap for the new Folktale library, and should land late 2017.

Human-readable textual representations of custom and built-in objects. No replacement exists yet, but this is in the roadmap for the new Folktale library, and should land late 2017.

Combinators and higher-order functions that are common in functional languages. Largely replaced by ES2015 features, with Base providing additional features. See the migration guide to update to Base.

Combinators and functions to ease using monads for control-flow. No replacement exists yet, but this is in the roadmap for the new Folktale library, and should land late 2017.

Additional functions for Task. With the new Folktale library this has been merged in Task. See the migration guide if you're using it.

A structure commonly used for computations that may fail. Either is now Result, to emphasise that use. See the migration guide if you're using it.

A structure for values that may or may not be present. In the new Folktale library with the same name. See the migration guide if you're using it.

A structure for pure, asynchronous actions. In the new Folktale library with the same name. See the migration guide if you're using it.

A structure for composable validations. In the new Folktale library with the same name. See the migration guide if you're using it.