CtrlK
BlogDocsLog inGet started
Tessl Logo

tessl/maven-io-arrow-kt--arrow-core-iosarm64

Functional companion to Kotlin's Standard Library - Core module with iosArm64 target support

—

Pending
Quality

Pending

Does it follow best practices?

Impact

Pending

No eval scenarios have been run

SecuritybySnyk

Pending

The risk profile of this skill

Overview
Eval results
Files

Arrow Core

Arrow Core is the foundational module of the Arrow Kotlin library that provides essential data types and functional programming abstractions for Kotlin Multiplatform development. It offers type-safe alternatives to null values, railway-oriented programming for error handling, non-empty collections, and a powerful Raise DSL for typed error management.

Package Information

  • Package Name: io.arrow-kt:arrow-core
  • Package Type: maven
  • Language: Kotlin
  • Platform: Kotlin Multiplatform (iosArm64, jvm, js, native targets)
  • Installation: implementation("io.arrow-kt:arrow-core:2.1.2")

Core Imports

import arrow.core.*
import arrow.core.raise.*

For specific imports:

import arrow.core.Either
import arrow.core.Option
import arrow.core.NonEmptyList
import arrow.core.raise.either
import arrow.core.raise.effect

Basic Usage

import arrow.core.*
import arrow.core.raise.either

// Working with Optional values
val maybeUser: Option<String> = Some("Alice")
val greeting = maybeUser.map { "Hello, $it!" }.getOrElse { "Hello, Guest!" }

// Error handling with Either
val result: Either<String, Int> = either {
    val input = "42"
    input.toIntOrNull() ?: raise("Invalid number")
}

// Non-empty collections
val numbers = nonEmptyListOf(1, 2, 3, 4, 5)
val doubled = numbers.map { it * 2 }

// Using the Raise DSL for error accumulation
val validation = either {
    val name = validateName("") // raises error if empty
    val age = validateAge(-1)   // raises error if negative
    User(name, age)
}

Architecture

Arrow Core is built around several key components:

  • Type-Safe Null Handling: Option<A> provides a safe alternative to nullable types
  • Railway-Oriented Programming: Either<A, B> enables clean error handling without exceptions
  • Error Accumulation: Ior<A, B> allows collecting multiple errors while preserving successful computations
  • Guaranteed Non-Empty Collections: NonEmptyList and NonEmptySet prevent empty collection errors at compile time
  • Raise DSL: A composable system for typed error handling with short-circuiting and accumulation
  • Effect System: Suspended computations with error handling capabilities
  • Functional Extensions: Rich collection operations following functional programming principles

Capabilities

Core Data Types

Essential functional data types providing type-safe alternatives to nullable values, error handling, and guaranteed non-empty collections.

sealed class Either<out A, out B>
sealed class Option<out A>
sealed class Ior<out A, out B>
interface NonEmptyCollection<out E>: Collection<E>
data class NonEmptyList<out A>: NonEmptyCollection<A>
data class NonEmptySet<out A>: NonEmptyCollection<A>

Core Data Types

Raise DSL

Composable typed error handling system with short-circuiting and error accumulation capabilities. Includes the Effect system for asynchronous computations and RaiseAccumulate for error collection. The foundation for all error handling in Arrow.

@RaiseDSL
interface Raise<in Error> {
    fun raise(error: Error): Nothing
    fun <A> Either<Error, A>.bind(): A
    fun <A> Option<A>.bind(): A
}

class SingletonRaise<in Error>: Raise<Error>
class IorRaise<Error>: Raise<Error>
class RaiseAccumulate<Error>: Raise<NonEmptyList<Error>>

// Effect System types
typealias Effect<Error, A> = suspend Raise<Error>.() -> A
typealias EagerEffect<Error, A> = Raise<Error>.() -> A

suspend fun <Error, A> effect(block: suspend Raise<Error>.() -> A): Either<Error, A>
fun <Error, A> eagerEffect(block: Raise<Error>.() -> A): Either<Error, A>

Raise DSL

Effect System

Suspended computations that can raise typed errors, providing a foundation for asynchronous and concurrent programming with proper error handling.

typealias Effect<Error, A> = suspend Raise<Error>.() -> A
typealias EagerEffect<Error, A> = Raise<Error>.() -> A

suspend fun <Error, A> effect(block: suspend Raise<Error>.() -> A): Either<Error, A>
fun <Error, A> eagerEffect(block: Raise<Error>.() -> A): Either<Error, A>
suspend fun <Error, A> Effect<Error, A>.fold(onError: (Error) -> A, onSuccess: (A) -> A): A

Effect System

Collection Extensions

Functional programming extensions for Kotlin collections including multi-parameter zip operations, alignment operations, error accumulation, and safety utilities.

fun <A, B, C, R> Iterable<A>.zip(other1: Iterable<B>, other2: Iterable<C>, transform: (A, B, C) -> R): List<R>
fun <Error, A, B> RaiseAccumulate<Error>.Iterable<A>.mapOrAccumulate(transform: Raise<Error>.(A) -> B): List<B>
fun <A, B> Iterable<A>.align(other: Iterable<B>): List<Ior<A, B>>
fun <A> Iterable<A>.firstOrNone(): Option<A>

Collection Extensions

Tuple Types

Immutable tuple data types for grouping 4-9 related values with type safety and destructuring support.

data class Tuple4<out A, out B, out C, out D>(val first: A, val second: B, val third: C, val fourth: D)
data class Tuple5<out A, out B, out C, out D, out E>(val first: A, val second: B, val third: C, val fourth: D, val fifth: E)
// ... through Tuple9
data class TupleN<out A>(val values: List<A>)

Tuple Types

Workspace
tessl
Visibility
Public
Created
Last updated
Describes
mavenpkg:maven/io.arrow-kt/arrow-core@2.1.x
Publish Source
CLI
Badge
tessl/maven-io-arrow-kt--arrow-core-iosarm64 badge