diff options
Diffstat (limited to 'compiler/parser')
| -rw-r--r-- | compiler/parser/HaddockParse.y | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/compiler/parser/HaddockParse.y b/compiler/parser/HaddockParse.y index e3f45f9475..d46223ddb3 100644 --- a/compiler/parser/HaddockParse.y +++ b/compiler/parser/HaddockParse.y @@ -9,7 +9,7 @@ module HaddockParse ( parseHaddockParagraphs, parseHaddockString, - MyEither(..) + EitherString(..) ) where import {-# SOURCE #-} HaddockLex @@ -35,7 +35,7 @@ import RdrName PARA { TokPara } STRING { TokString $$ } -%monad { MyEither String } +%monad { EitherString } %name parseHaddockParagraphs doc %name parseHaddockString seq @@ -98,15 +98,18 @@ strings :: { String } | STRING strings { $1 ++ $2 } { -happyError :: [Token] -> MyEither String a +happyError :: [Token] -> EitherString a happyError toks = MyLeft ("parse error in doc string") -- We don't want to make an instance for Either String, -- since every user of the GHC API would get that instance -data MyEither a b = MyLeft a | MyRight b +-- But why use non-Haskell98 instances when MyEither String +-- is the only MyEither we're intending to use anyway? --Isaac Dupree +--data MyEither a b = MyLeft a | MyRight b +data EitherString b = MyLeft String | MyRight b -instance Monad (MyEither String) where +instance Monad EitherString where return = MyRight MyLeft l >>= _ = MyLeft l MyRight r >>= k = k r |