Description

katamari is a collection of various data structures and reusable higher-order functions. It does not bundle any commands. It is only a collection of modules.

Installation

katamari is available as an npm package. You can install it via the npm package @ephox/katamari

Install from npm

npm install @ephox/katamari.

Usage

Note, refrain from using any modules that are not in the api package.

Below is a list of commonly used parts of katamari

Data Structures

Optional Data Types

• Optional: A representation of None or Some(x)
• Result: A representation of Error(str) or Value(v)

Asynchronous Data Types

• Future: An abstraction over an asynchronous value
• FutureResult: A composition of a Result and a Future
• LazyValue: An asynchronous value that is only calculated once

Mutable Data Types

• Cell: A mutable piece of data
• Singleton: A mutable piece of optional data

Algebraic Data Types

• Adt: An approximate representation of an Algebraic Data Type in JavaScript. It is based on the Church Encoding method.

Higher-order Functions

• Arr: collection of functions that operate on arrays
• Obj: collection of functions that operate on JavaScript objects
• Merger: collection of functions to merge JavaScript objects

Tests

katamari uses bedrock to run atomic tests. The tests are chiefly written using fast-check

Running Tests

$ yarn test

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog and this project adheres to Semantic Versioning.

Unreleased

9.1.0 - 2022-09-08

Added

• Added a Repeatable API to the Singleton module to repeat a function at a fixed interval.

Improved

• The Strings.contains API now accepts optional start and end parameters to set the range for searching within the string.
• The Obj APIs now use keyof T instead of string for the object key type.
• The Obj.filter API better handles type guard predicates so the return type matches the type guard.

9.0.0 - 2022-03-03

Added

• Added a new unique API to the Arr module to remove duplicate elements in an array.
• Added a new Type.is API to check if an object type matches the specified constructor type.

Changed

• Swapped Optional to be a class, instead of an object with function fields.

Improved

• Optional objects should now be faster to construct and work with.
• The Result and Optional APIs are now thoroughly documented.
• Added private .tag and .value properties to Result, to make them friendlier to view in the debugger or console.

Removed

• Removed support for Microsoft Internet Explorer and legacy Microsoft Edge.

8.1.0 - 2021-10-11

Added

• Added new Strings.toInt and Strings.toFloat APIs to be able to parse a string and convert it to a number.

8.0.0 - 2021-08-26

Added

• Added static Optionals.is and Optionals.equals methods.
• Added static Results.is method.

Removed

• Removed the .is, .equals and .equals_ APIs from Optional.
• Removed the .is API from Result.

Improved

• The Optional type is now covariant with respect to its type argument.
  • In particular, this means that if all Cats are Animals, then all Optional<Cat>s are now Optional<Animal>s.
• The Result type is now covariant with respect to its type argument.
• All singletons now have a get function that returns an Optional value.
• Arr.foldl and Arr.foldr now pass the item index in the callback function.

Fixed

• Throttler.adaptable could not re-throttle from within the callback function.

7.2.0 - 2021-05-06

Added

• Introduced Maybe as an eventual replacement for Optional.
• Added pipe function to the Fun API.

Changed

• Added type guard predicates to Arr.find methods #TINY-7138

7.1.0 - 2020-02-02

Added

• New Regex module

7.0.0

Removed

• Removed Struct. Please use TypeScript interfaces and functions instead.