Here I will be focused on problems of Scala only, Scala have number of benefits too but that will be in other post. I look at Scala from Java experience.
- Strict in type but loose in syntax ( meaning of syntax is unpredictable )
- Recursive functions could not be transformed by tail recursion, see blog of Rich Dougherty
- lists append , you need to remember to keep first list smaller then second to avoid performance problems
- scala is like a math formula, great when all is logical and all understand math easily, but real live is far from math.
- synax is unreadable sometime, it is like perl.
- syntax meaning is depends on linked libraries
- implicit converts from perspective of human investigation of code, so IDE have to be smart. Example Stting to StringOps.
-what is the reason to use in maps ++ instead of addAll.
-switching from val to var could make immutable set haver operators like +=.
- Great !!! Paul Phillips is a co-founder of Typesafe and the most prolific committer to Scala. His talk is about Scala problems: http://www.slideshare.net/extempore/a-scala-corrections-library
- Not only I afraid of all Scala abilities: http://www.thoughtworks.com/radar/#/languages-and-frameworks "Scala, the good part"
to be continued ....