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| author | Martin Odersky <odersky@gmail.com> | 2014-03-01 18:16:58 +0100 |
|---|---|---|
| committer | Martin Odersky <odersky@gmail.com> | 2014-03-01 18:16:58 +0100 |
| commit | 340ca0615bc40ca0232143b1d7e206c56e721c5c (patch) | |
| tree | 0a648f4ff290bbd1919ca705c3f6e6288f4bbd64 /src/dotty/tools/dotc/core/Types.scala | |
| parent | d8356b6dc9221bfc38b1f167e5cfafcc9261f3d7 (diff) | |
| download | dotty-340ca0615bc40ca0232143b1d7e206c56e721c5c.tar.gz dotty-340ca0615bc40ca0232143b1d7e206c56e721c5c.tar.bz2 dotty-340ca0615bc40ca0232143b1d7e206c56e721c5c.zip | |
Fixing glb/lub of TypeBounds
Need to take variances into account when forming & or | of bounds. Achieved by moving code from distributeAnd/Or to TypeBounds &/|.
Diffstat (limited to 'src/dotty/tools/dotc/core/Types.scala')
| -rw-r--r-- | src/dotty/tools/dotc/core/Types.scala | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala index 6973af726..1aaa85481 100644 --- a/src/dotty/tools/dotc/core/Types.scala +++ b/src/dotty/tools/dotc/core/Types.scala @@ -1883,11 +1883,21 @@ object Types { def contains(tp: Type)(implicit ctx: Context) = lo <:< tp && tp <:< hi - def & (that: TypeBounds)(implicit ctx: Context): TypeBounds = - derivedTypeBounds(this.lo | that.lo, this.hi & that.hi, this commonVariance that) + def & (that: TypeBounds)(implicit ctx: Context): TypeBounds = { + val v = this commonVariance that + if (v != 0 && (this.lo eq this.hi) && (that.lo eq that.hi)) + if (v > 0) derivedTypeAlias(this.hi & that.hi, v) + else derivedTypeAlias(this.lo | that.lo, v) + else derivedTypeBounds(this.lo | that.lo, this.hi & that.hi, v) + } - def | (that: TypeBounds)(implicit ctx: Context): TypeBounds = - derivedTypeBounds(this.lo & that.lo, this.hi | that.hi, this commonVariance that) + def | (that: TypeBounds)(implicit ctx: Context): TypeBounds = { + val v = this commonVariance that + if (v == 0 && (this.lo eq this.hi) && (that.lo eq that.hi)) + if (v > 0) derivedTypeAlias(this.hi | that.hi, v) + else derivedTypeAlias(this.lo & that.lo, v) + else derivedTypeBounds(this.lo & that.lo, this.hi | that.hi, v) + } override def & (that: Type)(implicit ctx: Context) = that match { case that: TypeBounds => this & that |