Point-Free

The hkt-toolbelt now provides a way to ‘reify’ a higher-order type into a concrete function type. This is useful for representation of point-free code. to reify: make (something abstract) more concrete or real. Basics of Higher-Order Types For the purposes of hkt-toolbelt, a higher-order type is merely a representation of a type mapping, i.e. an ‘applicable’ type that maps from an input type to an output type. Higher-order types are useful because they can take in higher order types, or return higher order types.

In Typescript, point-free programming has been traditionally limited due to the difficulty the type system has representing the abstracted types associated with point-free (also called ’tacit’) programming. 1. What is Tacit Programming? 2. Type-Level Programming 2.1. The Hard (Naive) Way 2.2. Tacit Logic via HKTs 3. Addendum: Library 3.1. Basic HKT Abstractions 3.2. HKT Composition 3.3. Narrow Type Inference 3.4. Value-level Apply 3.5. Auto-applyable HKTs 3.6. HKT-Level Flow 3.7. HKT-level Split 3.