TypeApplications error message doesn't parenthesize infix name
If you compile the following program:
module Bug where
f :: (Int -> Int) -> (Int -> Int) -> (Int -> Int)
f = (.) @Int
You'll get this error:
$ /opt/ghc/8.4.3/bin/ghc Bug.hs
[1 of 1] Compiling Bug ( Bug.hs, Bug.o )
Bug.hs:4:6: error:
Pattern syntax in expression context: .@Int
Did you mean to enable TypeApplications?
|
4 | f = (.) @Int
| ^^^^^^^^
I was taken aback by this strange .@
thing before I realized what was actually going on: the error message simply forgot to parenthesize .
. This is ppr_expr
's fault, since it calls ppr
on an RdrName
instead of pprPrefixOcc
. Patch incoming.
Trac metadata
Trac field | Value |
---|---|
Version | 8.4.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |