On 01/25/2013 12:23 AM, Adam Wilson wrote:
...
But what happens if t.baz returns a delegate?
You mean, a parameterless delegate. How many times does this occur that
it supports nuking a entire language feature?
Because properties, which conceptually have nothing to do with
functions, are implemented as functions they have the same optional
parens rules as functions.
Because the compiler is broken.
The problem is that they aren't intended to
be used as functions so in the case of delegate, you get massive
explosions in the compiler. For something that should be
straight-forward. If t.baz is a delegate than t.baz() should call the
DELEGATE, but it doesn't...
It should for @properties.
Optional Parens Encourage Ambiguity.
We could talk about fixing that particular situation, eg, only allow
paren-free calls when no parameterless callable is returned, with a very
explicit error message. (Like Jesse suggests as well.)
However, note that scala does the same we do now:
scala> def foo()=()=>2
foo: ()() => Int
scala> foo
res1: () => Int = <function0>
scala> foo()
res2: () => Int = <function0>
scala> foo()()
res3: Int = 2
I do not think this is a recurring discussion topic on the scala
newsgroup. I think we might actually be fine.
Ambiguity Fosters Bugs.
Delegates not being called is noticed quickly.
