Revert <: Product requierment in pattern matching #2249
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The change in question broke the following pattern, commonly used in name based pattern matching:
```scala
object ProdEmpty {
def _1: Int = ???
def _2: String = ???
def isEmpty = true
def get = this
}
```
This type define both `_1` and `get` + `isEmpty` (but is not <: Product). After scala#1938, `ProdEmpty` became eligibles for both product and name based pattern. Because "in case of ambiguities, *Product Pattern* is preferred over *Name Based Pattern*", isEmpty wouldn't be used, breaking the scalac semantics.
OlivierBlanvillain
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LGTM |
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The change in question broke the following pattern, commonly used in name based pattern matching:
This type define both
_1andget+isEmpty(but is not <: Product). After #1938,ProdEmptybecame eligibles for both product and name based pattern. Because "in case of ambiguities, Product Pattern is preferred over Name Based Pattern", isEmpty wouldn't be used, breaking the scalac semantics.Since this issue is blocker for cross compiling the back-end, I propose to first merge the revert, and discuss possible alternatives later.