Copyright | (c) Niklas Broberg 2009 |
---|---|

License | BSD-style (see the file LICENSE.txt) |

Maintainer | Niklas Broberg, d00nibro@chalmers.se |

Stability | stable |

Portability | portable |

Safe Haskell | Safe |

Language | Haskell98 |

Fixity information to give the parser so that infix operators can be parsed properly.

# Fixity representation

Operator fixities are represented by their associativity (left, right or none) and their precedence (0-9).

## Instances

Eq Fixity Source # | |

Data Fixity Source # | |

Defined in Language.Haskell.Exts.Fixity gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Fixity -> c Fixity # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Fixity # toConstr :: Fixity -> Constr # dataTypeOf :: Fixity -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Fixity) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Fixity) # gmapT :: (forall b. Data b => b -> b) -> Fixity -> Fixity # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Fixity -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Fixity -> r # gmapQ :: (forall d. Data d => d -> u) -> Fixity -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Fixity -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Fixity -> m Fixity # | |

Ord Fixity Source # | |

Show Fixity Source # | |

The following three functions all create lists of fixities from textual representations of operators. The intended usage is e.g.

fixs = infixr_ 0 ["$","$!","`seq`"]

Note that the operators are expected as you would
write them infix, i.e. with ` characters surrounding
*varid* operators, and *varsym* operators written as is.

## Collections of fixities

preludeFixities :: [Fixity] Source #

All fixities defined in the Prelude.

baseFixities :: [Fixity] Source #

All fixities defined in the base package.

Note that the `+++`

operator appears in both Control.Arrows and
Text.ParserCombinators.ReadP. The listed precedence for `+++`

in
this list is that of Control.Arrows.

# Applying fixities to an AST

class AppFixity ast where Source #

All AST elements that may include expressions which in turn may need fixity tweaking will be instances of this class.

:: Monad m | |

=> [Fixity] | The fixities to account for. |

-> ast SrcSpanInfo | The element to tweak. |

-> m (ast SrcSpanInfo) | The same element, but with operator expressions updated, or a failure. |

Tweak any expressions in the element to account for the fixities given. Assumes that all operator expressions are fully left associative chains to begin with.