Empfohlen
Empfohlen
Weitere ähnliche Inhalte
Was ist angesagt?
Was ist angesagt? (20)
Andere mochten auch
Ähnlich wie Functional Groovy - Confess
Ähnlich wie Functional Groovy - Confess (20)
Mehr von Andres Almiray
Mehr von Andres Almiray (20)
Kürzlich hochgeladen
Kürzlich hochgeladen (20)
Functional Groovy - Confess
- 1. FUNCTIONAL GROOVY ANDRES ALMIRAY ANDRES.ALMIRAY@CANOO.COM @AALMIRAY
- 2. ABOUT THE SPEAKER Java developer since the beginning True believer in open source Groovy committer since 2007 Project lead of the Griffon framework Currently working for
- 6. GROOVY IS NOT HASKELL RUSSEL WINDER
- 7. CLOSURES == FUNCTIONS Closures are functions (i.e, blocks of code) with an environment containing a binding for all free variables of the function
- 8. CLOSURES == FUNCTIONS Closures are NOT side effect free by design
- 9. CLOSURES: PARAMETERS (1) Parameter types may be omitted if type information is not needed
- 10. CLOSURES: PARAMETERS (2) Parameters may have default values NOTE: Default values must be defined from right to left
- 11. CLOSURES: DEFAULT PARAMETER Closures may have a default parameter named it
- 12. CLOSURES LEAD TO … Iterators Streams Partial Evaluation Composition Memoization Tail calls
- 13. ITERATORS (1)
- 14. ITERATORS (2) p
- 15. ITERATORS
- 16. GEEKS & BEERS Functional Java Lambdaj Google Guava
- 17. USE CASES Given a list of beers and their prices: Find the cheapest beer Find the most expensive beer What’s the name of the most expensive beer Get all the beer names What’s the total price
- 18. USE CASE 1 Find the cheapest beer
- 19. USE CASE 2 Find the most expensive beer
- 20. USE CASE 3 What’s the name of the most expensive beer
- 21. USE CASE 4 Get all the beer names
- 22. USE CASE 5 What’s the total price
- 23. PROS & CONS Java collections Non-lazy evaluation Closures! Streams not Plays nice with all included in core other functional filter/map/reduce frameworks Metaprogramming!
- 24. S/COLLECT/MAP/ Don’t like collect? Use Groovy’s metaprogramming
- 25. STREAMS (1) Lazy generators. Extension module created by @tim_yates http://timyates.github.com/groovy-stream/
- 26. STREAMS (2) Groovy is Java friendly. Use any Java library such as functional-java
- 28. STREAMS (JDK8) Collection and Lambda friendly, lazy evaluation
- 30. PARTIAL EVALUATION (1) Currying creates a new closure with fixed parameters, left to right
- 31. PARTIAL EVALUATION (2) Currying may be applied right to left too, even on an arbitrary index
- 32. OBJECTS AS PARTIAL EVALS Any class may implement the call() method, enabling implicit evaluation
- 33. COMPOSITION (1) Closures may be composed (left to right) using the >> operator
- 34. COMPOSITION (2) Closures may be composed (right to left) using the << operator
- 35. MEMOIZATION Cache computed values for increased performance
- 36. TAIL CALLS (1) Recursive closures may use Tail Calls thanks to trampoline()
- 37. TAIL CALLS (2) Apply @TailRecursive on methods https://github.com/jlink/tailrec/
- 38. METHODS AS CLOSURES Any method may be transformed to a Closure using the .& operator
- 39. IMMUTABILITY The @Immutable AST transformation makes writing immutable classes trivial
- 40. GPARS http://gpars.codehaus.org/ Concurrent collection processing Composable asynchronous functions Fork/Join abstraction Actor programming model Dataflow concurrency constructs CSP Agent - an thread-safe reference to mutable state
- 41. PARALLEL COLLECTIONS Gpars enhances JDK/GDK collections with parallel execution enabled versions
- 43. RESOURCES • http://pragprog.com/magazines/2013-01/using- memoization-in-groovy • http://www.ibm.com/developerworks/views/java/ libraryview.jsp?search_by=functional+thinking • https://github.com/jlink/tailrec/ • http://timyates.github.com/groovy-stream • http://www.jroller.com/vaclav • http://gpars.codehaus.org • http://www.slideshare.net/arturoherrero/functional- programming-with-groovy
- 44. HTTP://PEOPLE.CANOO.COM/SHARE ANDRES ALMIRAY ANDRES.ALMIRAY@CANOO.COM @AALMIRAY