5 files changed, 111 insertions, 19 deletions
diff --git a/lib/Language/Elna/AST.hs b/lib/Language/Elna/AST.hs
index 3189469..189fcb5 100644
--- a/lib/Language/Elna/AST.hs
+++ b/lib/Language/Elna/AST.hs
@@ -12,34 +12,20 @@ module Language.Elna.AST
 
 import Data.Int (Int32)
 import Data.List (intercalate)
-import Data.Word (Word16)
-import Data.Text (Text)
-import qualified Data.Text as Text
+import Data.Word (Word16, Word32)
 import Data.Char (chr)
-import Data.String (IsString(..))
+import Language.Elna.Location (Identifier(..), showArrayType)
 import Numeric (showHex)
 
-newtype Identifier = Identifier { unIdentifier :: Text }
-    deriving Eq
-
-instance Show Identifier
-  where
-    show (Identifier identifier) = Text.unpack identifier
-
-instance IsString Identifier
-  where
-    fromString = Identifier . Text.pack
-
 data TypeExpression
     = NamedType Identifier
-    | ArrayType TypeExpression Int32
+    | ArrayType Word32 TypeExpression
     deriving Eq
 
 instance Show TypeExpression
   where
     show (NamedType typeName) = show typeName
-    show (ArrayType typeName elementCount) = concat
-        [show typeName, "[", show elementCount, "]"]
+    show (ArrayType elementCount typeName) = showArrayType elementCount typeName
 
 data Literal
     = IntegerLiteral Int32
diff --git a/lib/Language/Elna/Location.hs b/lib/Language/Elna/Location.hs
new file mode 100644
index 0000000..918ef46
--- /dev/null
+++ b/lib/Language/Elna/Location.hs
@@ -0,0 +1,58 @@
+module Language.Elna.Location
+    ( Identifier(..)
+    , Location(..)
+    , Node(..)
+    , showArrayType
+    ) where
+
+import Data.Hashable (Hashable(..))
+import Data.String (IsString(..))
+import Data.Text (Text)
+import qualified Data.Text as Text
+import Data.Word (Word32)
+
+data Location = Location
+    { line :: Word32
+    , column :: Word32
+    } deriving (Eq, Show)
+
+instance Semigroup Location
+  where
+    (Location thisLine thisColumn) <> (Location thatLine thatColumn) = Location
+        { line = thisLine + thatLine
+        , column = thisColumn + thatColumn
+        }
+
+instance Monoid Location
+  where
+   mempty = Location{ line = 1, column = 1 }
+
+data Node a = Node a Location
+    deriving (Eq, Show)
+
+instance Functor Node
+  where
+    fmap f (Node node location) = Node (f node) location
+
+newtype Identifier = Identifier { unIdentifier :: Text }
+    deriving Eq
+
+instance Show Identifier
+  where
+    show (Identifier identifier) = Text.unpack identifier
+
+instance IsString Identifier
+  where
+    fromString = Identifier . Text.pack
+
+instance Ord Identifier
+  where
+    compare (Identifier lhs) (Identifier rhs) = compare lhs rhs
+
+instance Hashable Identifier
+  where
+    hashWithSalt salt (Identifier identifier) = hashWithSalt salt identifier
+
+showArrayType :: Show a => Word32 -> a -> String
+showArrayType elementCount typeName = concat
+    ["array[", show elementCount, "] of ", show typeName]
diff --git a/lib/Language/Elna/NameAnalysis.hs b/lib/Language/Elna/NameAnalysis.hs
new file mode 100644
index 0000000..7388851
--- /dev/null
+++ b/lib/Language/Elna/NameAnalysis.hs
@@ -0,0 +1,3 @@
+module Language.Elna.NameAnalysis
+    (
+    ) where
diff --git a/lib/Language/Elna/Parser.hs b/lib/Language/Elna/Parser.hs
index 109f1ba..23e09d9 100644
--- a/lib/Language/Elna/Parser.hs
+++ b/lib/Language/Elna/Parser.hs
@@ -80,7 +80,7 @@ typeExpressionP = arrayTypeExpression
     <|> NamedType <$> identifierP
     <?> "type expression"
   where
-    arrayTypeExpression = flip ArrayType
+    arrayTypeExpression = ArrayType
         <$> (symbol "array" *> bracketsP (lexeme Lexer.decimal))
         <*> (symbol "of" *> typeExpressionP)
 
diff --git a/lib/Language/Elna/SymbolTable.hs b/lib/Language/Elna/SymbolTable.hs
new file mode 100644
index 0000000..a33df44
--- /dev/null
+++ b/lib/Language/Elna/SymbolTable.hs
@@ -0,0 +1,45 @@
+module Language.Elna.SymbolTable
+    ( Info(..)
+    , ParameterInfo(..)
+    , SymbolTable(..)
+    , Type(..)
+    , booleanType
+    , intType
+    ) where
+
+import Data.HashMap.Strict (HashMap)
+import Data.Text (Text)
+import Data.Vector (Vector)
+import Data.Word (Word32)
+import Language.Elna.Location (Identifier(..), showArrayType)
+
+data Type
+    = PrimitiveType Text
+    | ArrayType Word32 Type
+    deriving Eq
+
+instance Show Type
+  where
+    show (PrimitiveType typeName) = show typeName
+    show (ArrayType elementCount typeName) = showArrayType elementCount typeName
+
+intType :: Type
+intType = PrimitiveType "int"
+
+booleanType :: Type
+booleanType = PrimitiveType "boolean"
+
+newtype SymbolTable = SymbolTable (HashMap Identifier Info)
+    deriving (Eq, Show)
+
+data ParameterInfo = ParameterInfo
+    { name :: Identifier
+    , type' :: Type
+    , isReferenceParameter :: Bool
+    } deriving (Eq, Show)
+
+data Info
+    = TypeInfo Type
+    | VariableInfo Type Bool
+    | ProcedureInfo SymbolTable (Vector ParameterInfo)
+    deriving (Eq, Show)