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explicitly bidirectional patterns should not report Recursive definition" when used in view pattern expression position

Compile this

pattern One <- ((==One) -> True)
  where One = 1

I get

test.hs:1:1: error:  
    Recursive pattern synonym definition with following bindings:
      One (defined at test.hs:(1,1)-(1,15))
  |
Compilation failed.

Note that the error is due to the usage in view pattern **expression position**.

But for explicitly bidirectional patterns, there is no recursivity going on. So this usage should be allowed.

I am testing with HEAD, but the issue is probably older.

Trac metadata
Trac field Value
Version 8.3
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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