The -> in ViewPatterns binds more weakly than infix data constructors.
The following code, essentially taken from the ViewPatterns page on the wiki doesn't seem to parse correctly.
mymap f [] = []
mymap f (x : mymap f -> xs) = f x : xsHowever, this does:
mymap f [] = []
mymap f (x : (mymap f -> xs)) = f x : xs(though it triggers bug #2395 (closed) about overlapping patterns)
It would seem nicer to make the view pattern arrow bind tighter than any infix data constructors.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.10.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |