ApplicativeDo failed to desugar last line with pure $ <expr>
{-# LANGUAGE ApplicativeDo #-}
f m = do
x <- m 1
y <- m 2
return $ x + y
f should have type (Applicative f, Num a, Num b) => (a -> f b) -> f b but ghc considers f a monad
maybe similar with #11607 (closed)
Trac metadata
Trac field | Value |
---|---|
Version | 8.0.1-rc2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |