Gleam is a functional programming language that does not support having mutable state. As such, programmers often have to pass state around manually, threading it through functions via arguments and return values. This can become a bit repetitive and clumsy.
What if state could be 'threaded' through functions automatically, with a nice API that resembles mutable state? This is the central idea of act and the Action type.
type Action(result, state) = fn(state) -> #(state, result)
actis inspired by the (now outdated) gleam-eval package.gleam-evalis super cool, but only supports theResulttype and was not created with Gleam'susefeature in mind.
gleam add actDocumentation can be found at https://hexdocs.pm/act. A simple example lives in test/act_test.gleam.
gleam run # Run the project
gleam test # Run the tests