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Martijn Hoekstra
@martijnhoekstra
I'd say the same, but the spec surprised me before. Then again, if this is as specced, I'd argue it's a bug in the spec and the implementation both
Harrison Houghton
@hrhino
If x is a parameterless method defined in some template, and the same template contains a setter method x_= as member, then the assignment x = e is interpreted as the invocation x_=(e) of that setter method. Analogously, an assignment f.x = e to a parameterless method x is interpreted as the invocation f.x_=(e).
hmm, so, that's vaguely ambiguous since x is a symbol, not a name, but it doesn't explain what a "setter method" is
other than that in this case x's setter method is x_=

when it comes to imports,

If x is bound by an import clause, then the simple name x is taken to be equivalent to the qualified name to which x is mapped by the import clause.

which is also kinda ambiguous

but I would argue that on the whole, if some expression works with a non-renaming import, it should work with the renaming import modulo α-conversion of the name within the scope of the import
Martijn Hoekstra
@martijnhoekstra

If x is a parameterless method defined in some template, and the same template contains a setter method x_= as member

if you import rename x => y, that doesn't change that the template doesn't contain a setter method x_=

so I'd call it a bug in both spec and impl :D
Harrison Houghton
@hrhino
right...
although that's not the correct spot, because that's the bit that deals with class T { var x = 1 ; x = 2 }
the "analogously..." sentence is the applicable one
I would say it should define "setter method" as "the method in the same template with the name derived from x by appending _=", or something
segeljakt
@segeljakt
What type of polymorphism is:
def func[A,B,C](a: A, b: B, c: C) = ...
func(3, "abc", 'o')
Harrison Houghton
@hrhino
then the method has a setter method...
@klassegeljakt just your bog standard parametric polymorphism.
Martijn Hoekstra
@martijnhoekstra
I'll leave you to the specese. gl;hf
Harrison Houghton
@hrhino
nah
I'd rather just fix the bug, and let others write the specese
segeljakt
@segeljakt
ok, what type of polymorphism is
def func[T](l: T*) = ...
func(3, "abc", 'o')
Harrison Houghton
@hrhino
Exact same.
Parametric polymorphism is polymorphism done with type parameters, hence the name
Fabio Labella
@SystemFw
well, that case is weird
well, not weird
but not strictly parametric polymorphism either, it's interacting with variance and sub typing there
Harrison Houghton
@hrhino
as opposed to, say, inheritance polymorphism, which is done by having an interface as a superclass of everything you want to accept
ah, true
Fabio Labella
@SystemFw
basically in a language with no sub typing, that would be an example of parametric polymorphism that doesn't compile :)
ah, you changed it
now it doesn't compile in Scala either :)
segeljakt
@segeljakt
oh
is Seq not covariant?
Fabio Labella
@SystemFw
ah, with Seq yeah, it does
Martijn Hoekstra
@martijnhoekstra
T is inferred to be Any - so the question is also "what kind of polymorphism is def func(l: Any*) = ???; func(3, "abc", 'o')" - to which the answer is "that not polymorphism, that's just making me cry"
Fabio Labella
@SystemFw
yeah pretty much
segeljakt
@segeljakt
I thought the first one was first-class monomorphic and the second one was second-class polymorphic
I don’t know the terms strictly
Fabio Labella
@SystemFw
yeah, no
that doesn't make a lot of sense :)
Harrison Houghton
@hrhino

@martijnhoekstra

        if (treeInfo.mayBeVarGetter(varsym)) {
          lhs1 match {
            case treeInfo.Applied(Select(qual, name), _, _) =>
              val sel = Select(qual, name.setterName) setPos lhs.pos
              val app = Apply(sel, List(rhs)) setPos tree.pos
              return typed(app, mode, pt)

            case _ =>
          }
        }

so yeah, it's doing a naïve name-based lookup. if you don't feel like filing a bug, lmk and I will

segeljakt
@segeljakt
Second class = upcast to common supertype?
Fabio Labella
@SystemFw
no, that terminology doesn't really exist afaict
segeljakt
@segeljakt
"So here we have the crux of the problem — we can have first-class monomorphic function values and we can have second-class polymorphic methods, but we can’t have first-class polymorphic function values … at least we can’t with the standard Scala definitions. And yet it’s first-class polymorphic function values that we need to map over an HList … what to do?"
Fabio Labella
@SystemFw
no, first class polymorphism is a different thing
segeljakt
@segeljakt
ok
Fabio Labella
@SystemFw
it's a more advanced topic
but it's got nothing to do with what you are talking about
Martijn Hoekstra
@martijnhoekstra
@hrhino don't you give me that nme pos tpe app pt qual tr gobbledygook - I run Windows and I'm pretty sure those are just part of GNU powertools
Harrison Houghton
@hrhino
watch me. you get lhs and sel too
and my favourite, mk