TypeApp

A minimal helper library for ergonomic type applications in PureScript.

Overview

The TypeApp library is a small utility that allows you to use type application syntax with existing functions that take Proxy arguments, improving readability and ergonomics without breaking existing APIs.

PureScript's type application feature lets you write clearer and more concise code, but many core libraries still require passing Proxy values explicitly. This library provides a lightweight bridge by allowing you to wrap such functions using the @TypeApplications syntax.

-- Instead of:
reflectSymbol (Proxy :: Proxy "someSymbol")

-- You can now write:
reflectSymbol @"someSymbol"

Installation

TODO

Modules

TypeApp

module TypeApp (p, vta) where

import Type.Proxy (Proxy(..))

-- Convenient alias to construct a Proxy at the type level
p :: forall k (@a :: k). Proxy a
p = Proxy

-- Apply a function that expects a Proxy argument using type application
vta :: forall @a r. (Proxy a -> r) -> r
vta f = f p

Example usage

With Data.Symbol.reflectSymbol

import Data.Symbol.TypeApp (reflectSymbol)

-- Instead of reflectSymbol (Proxy :: Proxy "label")
reflectSymbol @"label"

Why this library?

While type applications are supported in the compiler, much of the ecosystem still relies on explicit Proxy usage. Large-scale migrations are costly and disruptive. This library offers:

• Opt-in type application usage
• No breaking changes to dependencies
• Better readability in application code

Naming

We chose vta ("via type application") over wrap to avoid clashing with common function names from libraries like Newtype.

Contributing

Have a commonly used function you’d like to see in type application style? Open a PR or issue! We're open to extending the library with opt-in wrappers for major libraries (e.g., Record, Data.Symbol, Type.Data, etc.).