Origami

Monadic folds for Scala

Eric TorreborreScalaSyd

™ @charlesofarrell

composition?reuse?

performance?

safety?

No exception, please!

finalization

foldinitia

lization state

stream fold

monadic context

zip

functor

contra-functor

for breaking out

side-effects!

natural transformation

closes resource!

fold with IO side-effects

sum=0,string=foldssum=5,string=aresum=8,string=great

sum=0,string=foldssum=5,string=aresum=8,string=great

observeWithState

Operators…

compositionreuse

performance

safety

implicits

break-out

monadic “fold”

not battle-teste

d!

http://www.haskellforall.com/2013/08/composable-streaming-folds.html

http://conal.net/blog/posts/another-lovely-example-of-type-class-morphisms

https://www.fpcomplete.com/user/edwardk/cellular-automata/part-2

http://squing.blogspot.com.au/2008/11/beautiful-folding.html

http://notes.backgroundsignal.com/Transducers.html

Thanks!