Sectioned hole oddities
#13050 (closed) added support for infix holes. However, it seems that the same support was not added for //sectioned// holes, as the following two examples demonstrate:
Left-sectioned holes technically work, although they are pretty-printed poorly:
f :: Int -> Int -> Int
f x y = (x `_`) y
GHCi, version 8.2.2: http://www.haskell.org/ghc/ :? for help
Loaded GHCi configuration from /home/rgscott/.ghci
[1 of 1] Compiling Main ( Bug.hs, interpreted )
Bug.hs:2:12: error:
• Found hole: _ :: Int -> Int -> Int
• In the expression: _
In the expression: \ x_ -> _ x x_ )
In the expression: ( \ x_ -> _ x x_ )) y
• Relevant bindings include
y :: Int (bound at Bug.hs:2:5)
x :: Int (bound at Bug.hs:2:3)
f :: Int -> Int -> Int (bound at Bug.hs:2:1)
|
2 | f x y = (x `_`) y
| ^^^
Notice the messy In the expression: \ x_ -> _ x x_ )
part.
Right-sectioned holes don't even parse at all:
f :: Int -> Int -> Int
f x y = (`_` x) y
GHCi, version 8.2.2: http://www.haskell.org/ghc/ :? for help
Loaded GHCi configuration from /home/rgscott/.ghci
[1 of 1] Compiling Main ( Bug.hs, interpreted )
Bug.hs:2:11: error: parse error on input ‘_’
|
2 | f x y = (`_` x) y
| ^
Trac metadata
Trac field | Value |
---|---|
Version | 8.2.2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |