Added haddock documentation

src/Semantic/TypeChecker.hs

@@ -3,6 +3,7 @@ module Semantic.TypeChecker where
 import Model.Type
 import Data.Either
 
+-- |A datatype for the different types of type check errors
 data TypeCheckError =
    UndefinedType String
    | IfConditionNotBoolean
@@ -13,6 +14,7 @@ data TypeCheckError =
    | TypeMismatch String String
    deriving (Show)
 
+-- |Checks whether a data type is valid
 checkType :: [Type] -> Type -> Either [TypeCheckError] Type
 checkType definedTypes (MakeType name super desc attr)
     | null (lefts checkedAttr) = Right $ MakeType name super desc (rights checkedAttr)
@@ -20,6 +22,8 @@ checkType definedTypes (MakeType name super desc attr)
     where checkedAttr = checkAttributes definedTypes attr 
 checkType _ (BasicType b) = Right (BasicType b)
 
+
+-- |Checks whether all the types of the attributes of a data type are already defined
 checkAttributes :: [Type] -> [TypeAttribute] -> [Either TypeCheckError TypeAttribute]
 checkAttributes _ [] = []
 checkAttributes definedTypes ((MakeTypeAttribute name typ crd desc):as)
@@ -27,6 +31,7 @@ checkAttributes definedTypes ((MakeTypeAttribute name typ crd desc):as)
     | otherwise = Left (fromLeftUnsafe checked) : checkAttributes definedTypes as
     where checked = checkAttributeType definedTypes typ 
 
+-- |Checks whether a type is predefined or in the symbol table
 checkAttributeType :: [Type] -> Type -> Either TypeCheckError Type
 checkAttributeType _ (MakeType "int" _ _ _) = Right $ BasicType "Integer"
 checkAttributeType _ (MakeType "string" _ _ _) = Right $ BasicType "String"
@@ -37,16 +42,21 @@ checkAttributeType definedTypes name
     | name `elem` definedTypes = Right name
     | otherwise = Left $ UndefinedType (typeName name)
     
+-- |Add a list of defined types to the symbol table
 addDefinedTypes :: [Type] -> [Type] -> [Type]
 addDefinedTypes l [] = l
 addDefinedTypes l (BasicType _ : ts) = addDefinedTypes l ts
 addDefinedTypes l (t:ts) = t : addDefinedTypes l ts
 
+-- |Auxiliary function to get the right value from an either that stops with an error if the value is left
+-- used when it is certain that the value will be right
 fromRightUnsafe :: (Show a) => Either a b -> b
 fromRightUnsafe x = case x of
     Left a -> error ("Value is Left" ++ show a)
     Right b -> b
     
+-- |Auxiliary function to get the left value from an either that stops with an error if the value is right
+-- used when it is certain that the value will be left
 fromLeftUnsafe :: Either a b -> a
 fromLeftUnsafe x = case x of
     Left a -> a