Ito, a new Lua library, lets developers build terminal interfaces in a SwiftUI-like style

Ito is a new library for building terminal user interfaces in Lua. The project describes itself as a declarative UI library, heavily inspired by SwiftUI.

Declarative means you describe what the screen should look like, and the library handles drawing it. You don't give it step-by-step drawing instructions. SwiftUI is Apple's framework for building app interfaces, and Ito borrows its overall style.

To get started, you load the library with require("ito") and return a function that builds a view. For values that change, such as a counter or a checkbox, you use ito.state(value). The project's documentation says views are composed from pieces like VStack, HStack and Text, plus the controls listed in a file called ito.md. A VStack stacks items vertically, and an HStack lines them up horizontally.

Styling is done by chaining methods onto a view. The examples use :spacing(1), :padding(2), :grow(), :bold() and :dim() to arrange and style things.

The project's example is a small shop screen for a notebook called "Field Notes" from "The Small Goods Shop". It has a heading, a price of $18, and plus and minus buttons that change the quantity between 1 and 9. There is also a checkbox to add gift wrap for $3, and an "Add to bag" button that shows the running total. The whole thing sits inside a rounded border.

The buttons in the example also carry accessibility labels, such as "Fewer notebooks" and "More notebooks".

The project also points to a way to try it in the browser. It is described as an interactive workshop with a live preview.