-
Notifications
You must be signed in to change notification settings - Fork 2
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #9 from objectionary/rule-1
- Loading branch information
Showing
18 changed files
with
378 additions
and
150 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,88 @@ | ||
| {-# LANGUAGE LambdaCase #-} | ||
| {-# LANGUAGE RecordWildCards #-} | ||
| module Language.EO.Phi.Rules.Common where | ||
|
|
||
| import Language.EO.Phi.Syntax.Abs | ||
| import Control.Applicative (asum, Alternative ((<|>))) | ||
|
|
||
| -- $setup | ||
| -- >>> :set -XOverloadedStrings | ||
| -- >>> import Language.EO.Phi.Syntax | ||
|
|
||
| data Context = Context | ||
| { allRules :: [Rule] | ||
| } | ||
|
|
||
| -- | A rule tries to apply a transformation to the root object, if possible. | ||
| type Rule = Context -> Object -> Maybe Object | ||
|
|
||
| applyOneRuleAtRoot :: Context -> Object -> [Object] | ||
| applyOneRuleAtRoot ctx@Context{..} obj = | ||
| [ obj' | ||
| | rule <- allRules | ||
| , Just obj' <- [rule ctx obj] | ||
| ] | ||
|
|
||
| withSubObject :: (Object -> [Object]) -> Object -> [Object] | ||
| withSubObject f root = f root <|> | ||
| case root of | ||
| Formation bindings -> | ||
| Formation <$> withSubObjectBindings f bindings | ||
| Application obj bindings -> asum | ||
| [ Application <$> withSubObject f obj <*> pure bindings | ||
| , Application obj <$> withSubObjectBindings f bindings | ||
| ] | ||
| ObjectDispatch obj a -> ObjectDispatch <$> withSubObject f obj <*> pure a | ||
| GlobalDispatch{} -> [] | ||
| ThisDispatch{} -> [] | ||
| Termination -> [] | ||
|
|
||
| withSubObjectBindings :: (Object -> [Object]) -> [Binding] -> [[Binding]] | ||
| withSubObjectBindings _ [] = [] | ||
| withSubObjectBindings f (b:bs) = asum | ||
| [ [ b' : bs | b' <- withSubObjectBinding f b ] | ||
| , [ b : bs' | bs' <- withSubObjectBindings f bs ] | ||
| ] | ||
|
|
||
| withSubObjectBinding :: (Object -> [Object]) -> Binding -> [Binding] | ||
| withSubObjectBinding f = \case | ||
| AlphaBinding a obj -> AlphaBinding a <$> withSubObject f obj | ||
| EmptyBinding{} -> [] | ||
| DeltaBinding{} -> [] | ||
| LambdaBinding{} -> [] | ||
|
|
||
| applyOneRule :: Context -> Object -> [Object] | ||
| applyOneRule = withSubObject . applyOneRuleAtRoot | ||
|
|
||
| isNF :: Context -> Object -> Bool | ||
| isNF ctx = null . applyOneRule ctx | ||
|
|
||
| -- | Apply rules until we get a normal form. | ||
| -- | ||
| -- >>> mapM_ (putStrLn . Language.EO.Phi.printTree) (applyRules (Context [rule6]) "⟦ a ↦ ⟦ b ↦ ⟦ ⟧ ⟧.b ⟧.a") | ||
| -- ⟦ ⟧ (ρ ↦ ⟦ ⟧) (ρ ↦ ⟦ ⟧) | ||
| applyRules :: Context -> Object -> [Object] | ||
| applyRules ctx obj | ||
| | isNF ctx obj = [obj] | ||
| | otherwise = | ||
| [ obj'' | ||
| | obj' <- applyOneRule ctx obj | ||
| , obj'' <- applyRules ctx obj' ] | ||
|
|
||
| applyRulesChain :: Context -> Object -> [[Object]] | ||
| applyRulesChain ctx obj | ||
| | isNF ctx obj = [[obj]] | ||
| | otherwise = | ||
| [ obj : chain | ||
| | obj' <- applyOneRule ctx obj | ||
| , chain <- applyRulesChain ctx obj' ] | ||
|
|
||
| -- * Helpers | ||
|
|
||
| -- | Lookup a binding by the attribute name. | ||
| lookupBinding :: Attribute -> [Binding] -> Maybe Object | ||
| lookupBinding _ [] = Nothing | ||
| lookupBinding a (AlphaBinding a' object : bindings) | ||
| | a == a' = Just object | ||
| | otherwise = lookupBinding a bindings | ||
| lookupBinding _ _ = Nothing |
Oops, something went wrong.