When is a scala partial function not a partial function?
- by Fred Haslam
While creating a map of String to partial functions I ran into unexpected behavior. When I create a partial function as a map element it works fine. When I allocate to a val it invokes instead. Trying to invoke the check generates an error. Is this expected? Am I doing something dumb? Comment out the check() to see the invocation. I am using scala 2.7.7
def PartialFunctionProblem() = {
def dream()() = {
println("~Dream~");
new Exception().printStackTrace()
}
val map = scala.collection.mutable.HashMap[String,()=>Unit]()
map("dream") = dream() // partial function
map("dream")() // invokes as expected
val check = dream() // unexpected invocation
check() // error: check of type Unit does not take parameters
}
