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Function references in Scala October 17, 2011

I’m starting to learn Scala, and have some trouble coming to terms with its syntax. Maybe I’m spoiled by Python. In any case, here’s an example of things that I find annoying:


scala> def f(x:Int):Int = x
f: (x: Int)Int

scala> def h=f
:6: error: missing arguments for method f in object $iw;
follow this method with `_' if you want to treat it as a partially applied function
def h=f
^
scala> def h=f _
h: (Int) => Int


So basically, although it is fine to use just f when defining function g, in the definition of function h it is necessary to postfix f with an underscore.

I haven’t read the language reference yet, and there may be good reasons to do it like this (although I can’t think of any right now), but the inconsistency is quite confusing.