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We're moving from Scala 2.7.7 to the new Scala 2.8, here are some issues we hit along the way:

• Referencing types in parent packages
  • In 2.7.7 it seems that the compiler would allow references to types in parent packages, e.g. if I was writing a class in package com.example.data.test, then I could reference types in com.example.data without importing them
  • In Scala 2.8 you have to explicitly import these
  • Makes sense, I wonder if this was a bug in 2.7.7 or a feature?
• Implicits on companions
  • I'm not 100% sure on this one
  • We have a number of companion objects with implicit conversions on them
  • In 2.7.7 we could use these implicits without explicitly importing them, but in 2.8 we have to import them
• Missing package scala.collection.jcl
  • We used this package in 2.7.7 for some conversions from Java collections to Scala collections
  • Its not present in 2.8
  • scala.collection.JavaCollections._ seems to work well instead
  • See: http://stackoverflow.com/questions/3444647/how-to-port-scala-2-7-7-code-that-uses-scala-collection-jcl-to-scala-2-8
• Implementing Iterable
  • In 2.7.7 we often implemented iterable like this: new Iterable[Int] { def elements = ... }
  • Instead, in 2.8, you need to write new Iterable[Int] { def iterator = ... }
• Adding pairs to a ListBuffer
  • In 2.7.7, this code worked:
    • val buf = new ListBuffer[(A,B)]
    • buf += (a, b)
  • In 2.8 it doesn't compile for me, I needed additional parens, e.g.
    • buf += ((a,b))