Tutorials

Each tutorial ends with a complete editable program, its checked output, and a source download. Choose Run to try your changes in the browser, or Debug to follow statement checkpoints. You can also run locally from the repository root with cargo run -- ks site/examples/NAME.ks.

Count words

Turn text into a frequency table with string normalization, arrays, a map, and explicit defaults for missing keys. This is a first program to try after the getting-started page.

You will learn how data moves between library types and why output ordering should be a deliberate choice.

Keep state in a closure

Build independent counters from one factory function. Follow the difference between creating a binding and updating a binding, then see why two returned functions can have separate state.

You will learn how lexical capture works without introducing an object or global counter.

Design a result-returning API

Divide a quantity among teams and people while making invalid inputs explicit. Define the operation’s contract, represent failure as data, propagate it through a second function, and render it at the boundary.

You will learn how Res, match, and ? fit together.

For shorter programs with less explanation, browse the example collection.