Skip to content

Gadt unification #5611

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 8 commits into from
Dec 17, 2018
Merged

Gadt unification #5611

Changes from 1 commit
Commits
Show all changes
8 commits
Select commit Hold shift + click to select a range
225aabc
Revert "Handle higher-kinded GADT bounds"
abgruszecki Dec 14, 2018
08ac0a0
Move TyperState.instType
abgruszecki Dec 14, 2018
04503d9
Allow overriding ConstraintHandling logs
abgruszecki Dec 14, 2018
4c41fc4
Reuse ConstraintHandling for GADTMap
abgruszecki Dec 14, 2018
de795a9
Add caching to GADTMap
abgruszecki Dec 14, 2018
6cca0a6
Clean up GADTMap#ctx
abgruszecki Dec 14, 2018
f75f58f
Address review comments
abgruszecki Dec 16, 2018
d1fa5d7
Simplify TypeComparer.explaining
abgruszecki Dec 17, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
21 changes: 12 additions & 9 deletions compiler/src/dotty/tools/dotc/core/ConstraintHandling.scala
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,9 @@ import config.Printers.{constr, typr}
*/
trait ConstraintHandling {

def constr_println(msg: => String): Unit = constr.println(msg)
def typr_println(msg: => String): Unit = typr.println(msg)

implicit val ctx: Context

protected def isSubType(tp1: Type, tp2: Type): Boolean
Expand Down Expand Up @@ -120,23 +123,23 @@ trait ConstraintHandling {
if (Config.failOnInstantiationToNothing) assert(false, msg)
else ctx.log(msg)
}
constr.println(i"adding $description$location")
constr_println(i"adding $description$location")
val lower = constraint.lower(param)
val res =
addOneBound(param, bound, isUpper = true) &&
lower.forall(addOneBound(_, bound, isUpper = true))
constr.println(i"added $description = $res$location")
constr_println(i"added $description = $res$location")
res
}

protected def addLowerBound(param: TypeParamRef, bound: Type): Boolean = {
def description = i"constraint $param >: $bound to\n$constraint"
constr.println(i"adding $description")
constr_println(i"adding $description")
val upper = constraint.upper(param)
val res =
addOneBound(param, bound, isUpper = false) &&
upper.forall(addOneBound(_, bound, isUpper = false))
constr.println(i"added $description = $res$location")
constr_println(i"added $description = $res$location")
res
}

Expand All @@ -149,20 +152,20 @@ trait ConstraintHandling {
val up2 = p2 :: constraint.exclusiveUpper(p2, p1)
val lo1 = constraint.nonParamBounds(p1).lo
val hi2 = constraint.nonParamBounds(p2).hi
constr.println(i"adding $description down1 = $down1, up2 = $up2$location")
constr_println(i"adding $description down1 = $down1, up2 = $up2$location")
constraint = constraint.addLess(p1, p2)
down1.forall(addOneBound(_, hi2, isUpper = true)) &&
up2.forall(addOneBound(_, lo1, isUpper = false))
}
constr.println(i"added $description = $res$location")
constr_println(i"added $description = $res$location")
res
}

/** Make p2 = p1, transfer all bounds of p2 to p1
* @pre less(p1)(p2)
*/
private def unify(p1: TypeParamRef, p2: TypeParamRef): Boolean = {
constr.println(s"unifying $p1 $p2")
constr_println(s"unifying $p1 $p2")
assert(constraint.isLess(p1, p2))
val down = constraint.exclusiveLower(p2, p1)
val up = constraint.exclusiveUpper(p1, p2)
Expand Down Expand Up @@ -260,7 +263,7 @@ trait ConstraintHandling {
case _: TypeBounds =>
val bound = if (fromBelow) constraint.fullLowerBound(param) else constraint.fullUpperBound(param)
val inst = avoidParam(bound)
typr.println(s"approx ${param.show}, from below = $fromBelow, bound = ${bound.show}, inst = ${inst.show}")
typr_println(s"approx ${param.show}, from below = $fromBelow, bound = ${bound.show}, inst = ${inst.show}")
inst
case inst =>
assert(inst.exists, i"param = $param\nconstraint = $constraint")
Expand Down Expand Up @@ -359,7 +362,7 @@ trait ConstraintHandling {
val lower = constraint.lower(param)
val upper = constraint.upper(param)
if (lower.nonEmpty && !bounds.lo.isRef(defn.NothingClass) ||
upper.nonEmpty && !bounds.hi.isRef(defn.AnyClass)) constr.println(i"INIT*** $tl")
upper.nonEmpty && !bounds.hi.isRef(defn.AnyClass)) constr_println(i"INIT*** $tl")
lower.forall(addOneBound(_, bounds.hi, isUpper = true)) &&
upper.forall(addOneBound(_, bounds.lo, isUpper = false))
case _ =>
Expand Down