Functional Groovy
Functional Groovy is a library for doing functional programming (FP) in Groovy. It is a Groovy extension module for Functional Java (FJ), adding Groovy idioms and new FP constructs in Groovy.
Features includes:
- FunctionalJava based
- Enhances FunctionalJava for Groovy as a Groovy extension module
- Groovy Quickcheck style property testing (specification based testing)
- Monad library using a minimal monad implementation (unit/flatMap)
- Monadic functions added to the standard Java List
- Monad comprehensions (dynamically typed)
- Lenses
- Reader, Writer and State monads
- A simple IO type
- Y Combinator
The project has some cloud build servers I used to experiment with including:
I have written an initial blog post on Groovy Null Handling using Bind, Comprehensions and Lift covering:
- some introductory material on functional programming in Groovy
- how to begin using the Functional Groovy library
- handling
null
s by binding through theOption
type, monadic comprehensions and monadic lifting
The full list of related posts are:
- Groovy Null Handling Using Bind, Comprehensions and Lift
- Specification Based Testing
- Referentially Transparent Input/Output in Groovy
- Folds and Unfolds
To start using the library add the dependency com.github.mperry:functionalgroovy-main:0.5.1-SNAPSHOT
to your Gradle project. A simple test script to get going (test.groovy
) is:
@GrabResolver('https://oss.sonatype.org/content/groups/public')
@Grab('com.github.mperry:functionalgroovy-core:0.5.1-SNAPSHOT')
@Grab('org.functionaljava:functionaljava:4.1')
import com.github.mperry.fg.*
1.to(5).each {
println it
}
Run this script using groovy test.groovy
.
This project uses:
- JDK 8
- Gradle 1.11
- Groovy 2.3.2
- Functional Java 4.1
- Intellij Community Edition 13.1
I have added a list of open issues so feel free to contribute. Some ways of contributing are:
- adding new functionality
- adding tests
- adding FP in Groovy examples
- adding FunctionalGroovy usage examples
Functional Groovy is divided into four components: core, main, demo, java8 and consume.
- Core enhances Functional Java with Groovy idioms
- Main adds new functionality
- Demo includes examples of FP in Groovy and usage of this library
- Java8 includes enhancements related to Java 8 types (e.g. Optional).
- Consume shows how to include FunctionalGroovy in your project