The KataScript Book

Learn KataScript by reading a small concept, changing a runnable program, and carrying that result into the next chapter.

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First programs

1. 01Syntax and valuesWrite an expression and see its value.
2. 02Bindings and scopeGive values names and track the scopes that hold them.
3. 03Control flow and patternsChoose and repeat work with conditions and loops.
4. 04Functions and closuresMake behavior reusable and carry a binding out of scope.
5. 05Project: stateful counterTest captured state with two independent counters.
6. 06FibonacciUse a loop invariant in a complete program.

Data and interfaces

7. 07Types and dataModel product, sum, tuple, and generic values.
8. 08Methods and interfacesAttach behavior to a type.
9. 09Strings and bytesShape text and binary data.
10. 10CollectionsStore, index, and iterate data.
11. 11Project: word frequencyNormalize text and count it.
12. 12Custom iteratorMake a type work with for.

Modules and errors

13. 13Modules and errorsImport code and make failure explicit.
14. 14Project: model a resultDesign an operation with an honest contract.
15. 15Result pipelinePractice propagation and pattern matching.

Keep Docs nearby for exact syntax, API contracts, and current implementation limits.