Open jad-hamza opened 4 years ago
I’d have thought that TypeEncoding would handle this properly, I’ll take a look!
Might be related to #666. Will attempt to fix both in #685.
The issue is that, after AdtSpecialization
, we get:
def f$30[T$37 <: A$85](a$6: T$37): Boolean = a$6.isInstanceOf[{ v$11: A$85 | v$11 is C$9 }]
(A
is rightly considered to be an ADT at this point)
Then, after RefinementLifting
:
def f$30[T$37 <: A$85](a$6: T$37): Boolean = a$6 is C$9
On current master
, after TypeEncoding
:
def f$30[T$37](a$6: T$37): Boolean = a$6 is C$9
which does not type-check, obviously, since a$6
is of generic type T$37
.
With #685 we get the following after TypeEncoding
:
abstract class A$85
case class C$9() extends A$85
@synthetic
abstract class Object$0
case class Open$0(value$5: BigInt) extends Object$0
def f$30(T$38: (x$83: Object$0) => { b$6: Boolean | @unchecked (b$6 ==> (x$83 is A$89 && true)) }, a$6: { x$84: Object$0 | @unchecked T$38(x$84) }): Boolean = {
a$6 is C$9
}
which does not type-check either because a$6
has type Object$0
, which is unrelated to C$9
.
I am not quite sure what to do about this, perhaps we should not specialize A
to an ADT, because of the bound T <: A
in f
, which would imply relying on functions' bodies to determine whether or not to specialize a class to an ADT.
Note that, even if we do not specialize A
, we get the following before/after TypeEncoding
on master:
// Before
def f$30[T$37 <: A$85](a$6: T$37): Boolean = a$6.isInstanceOf[C$9]
// After
def f$30[T$37](a$6: T$37): Boolean = false
which is wrong as well.
Whereas with #685, we get:
def f$30(T$38: (x$83: Object$0) => { b$6: Boolean | @unchecked (b$6 ==> isA$0(x$83)) }, a$6: { x$84: Object$0 | @unchecked T$38(x$84) }): Boolean = {
isC$0(a$6)
}
@unchecked @synthetic
def isA$0(x$86: Object$0): Boolean = isC$0(x$86)
@unchecked @synthetic
def isC$0(x$92: Object$0): Boolean = x$92 is C$9 && true
@synthetic
abstract class Object$0
case class C$9() extends Object$0
case class Open$0(value$5: BigInt) extends Object$0
which looks right and does indeed type-checks.
@jad-hamza @samarion What do you think?
PS: I have omitted the synthetic postcondition on f
for clarity.
Should we reject this upfront?