kamchatkaltd / okasaki Goto Github PK

http://apfelmus.nfshost.com/articles/monoid-fingertree.html

In Scala, r.reverse is strict; so we won't be able to discard the debits before it happens.

What we need is a very lazy ++, one that does not calculate its argument until the stream reaches it

SetSpec's val set has a type of Set[E, S]; what I would like to see is something more like SES <: Set[E, S] — but this breaks compilation somehow.

The offending code is:

object RedBlackSetSpec {
  val set = new RedBlackSet[Int]
}

class RedBlackSetSpec
  extends SetSpec(RedBlackSetSpec.set)
  with IntElements {

  val set = RedBlackSetSpec.set

  // ...
}

the ideal code would be something along the lines of,

class RedBlackSetSpec
  extends SetSpec(new RedBlackSet[Int])
  with IntElements {

  // ...
}

https://www.st.cs.uni-saarland.de/edu/seminare/2005/advanced-fp/docs/huet-zipper.pdf

http://hackage.haskell.org/package/containers-0.1.0.1/docs/Data-IntMap.html

http://cstheory.stackexchange.com/questions/1539/whats-new-in-purely-functional-data-structures-since-okasaki