- tr :: (MIMEType, [String]) -> [ (String, MIMEType) ]
- tr (mime, exts) = [ (ext, mime) | ext <- exts ]
-
--- |@'serializeExtMap' extMap moduleName variableName@ generates a
--- Haskell source code which contains the following things:
---
--- * A definition of module named @moduleName@.
---
--- * @variableName :: 'ExtMap'@ whose content is a serialization of
--- @extMap@.
---
--- The module "Network.HTTP.Lucu.MIMEType.DefaultExtensionMap" is
--- surely generated using this function.
-serializeExtMap :: ExtMap -> String -> String -> String
-serializeExtMap extMap moduleName variableName
- = let hsModule = HsModule undefined modName (Just exports) imports decls
- modName = Module moduleName
- exports = [HsEVar (UnQual (HsIdent variableName))]
- imports = [ HsImportDecl undefined (Module "Network.HTTP.Lucu.MIMEType") False Nothing Nothing
- , HsImportDecl undefined (Module "Network.HTTP.Lucu.MIMEType.Guess") False Nothing Nothing
- , HsImportDecl undefined (Module "Data.Map") True (Just (Module "M")) Nothing
- , HsImportDecl undefined (Module "Data.Map") False Nothing (Just (False, [HsIAbs (HsIdent "Map")]))
- ]
- decls = [ HsTypeSig undefined [HsIdent variableName]
- (HsQualType []
- (HsTyCon (UnQual (HsIdent "ExtMap"))))
- , HsFunBind [HsMatch undefined (HsIdent variableName)
- [] (HsUnGuardedRhs extMapExp) []]
- ]
- extMapExp = HsApp (HsVar (Qual (Module "M") (HsIdent "fromList"))) (HsList records)
- comment = "{- !!! WARNING !!!\n"
- ++ " This file is automatically generated.\n"
- ++ " DO NOT EDIT BY HAND OR YOU WILL REGRET -}\n\n"
- in
- comment ++ prettyPrint hsModule ++ "\n"
- where
- records :: [HsExp]
- records = map record $ M.assocs extMap
-
- record :: (String, MIMEType) -> HsExp
- record (ext, mime)
- = HsTuple [HsLit (HsString ext), mimeToExp mime]
-
- mimeToExp :: MIMEType -> HsExp
- mimeToExp (MIMEType maj min params)
- = foldl appendParam (HsInfixApp
- (HsLit (HsString maj))
- (HsQVarOp (UnQual (HsSymbol "</>")))
- (HsLit (HsString min))) params
-
- appendParam :: HsExp -> (String, String) -> HsExp
- appendParam x param
- = HsInfixApp x (HsQVarOp (UnQual (HsSymbol "<:>"))) $ paramToExp param
-
- paramToExp :: (String, String) -> HsExp
- paramToExp (name, value)
- = HsInfixApp
- (HsLit (HsString name))
- (HsQVarOp (UnQual (HsSymbol "<=>")))
- (HsLit (HsString value))
\ No newline at end of file
+ tr ∷ (v, [k]) → [(k, v)]
+ tr (v, ks) = [(k, v) | k ← ks]
+
+ go ∷ Ord k ⇒ Map k v → [(k, v)] → Either (k, v, v) (Map k v)
+ go m [] = Right m
+ go m ((k, v):xs)
+ = case M.insertLookupWithKey' f k v m of
+ (Nothing, m') → go m' xs
+ (Just v0, _ ) → Left (k, v0, v)
+
+ f ∷ k → v → v → v
+ f _ _ = id
+
+-- |Guess the MIME Type of a file.
+guessTypeByFileName ∷ ExtMap → FilePath → Maybe MIMEType
+guessTypeByFileName (ExtMap m) fpath
+ = case takeExtension fpath of
+ [] → Nothing
+ (_:ext) → M.lookup (T.pack ext) m