nearly repaired parser but need to create switch test case

TODO.md

@@ -6,8 +6,7 @@
  - [ ] need canonical form making it easy to run all these validation 
        passes
  - [ ] are recursive slices inclusive?
- - [ ] what are the semantics of connection `<conn-stmt>`? Where is 
-       `<conn-stmt>` employed?
+ - [ ] what are the semantics of connection `<conn-stmt>`?
  - [ ] Validate that `123456789[0:9][0:8]` is valid RTLIL
  - [ ] add validation section to README
  - [ ] just support Cell memV2

src/RTLILParser/AST.hs

@@ -72,7 +72,7 @@ data Value = Value
 -- strings
 -- comments
 -- file
-data File           = File AutoIdxStmt [Module] deriving (Show)
+data File           = File (Maybe AutoIdxStmt) [Module] deriving (Show)
 
 -- Autoindex statements
 data AutoIdxStmt    = AutoIdxStmt   Int     deriving (Show)
@@ -81,11 +81,12 @@ data AutoIdxStmt    = AutoIdxStmt   Int     deriving (Show)
 data Module         = Module ModuleStmt [AttrStmt] ModuleBody deriving (Show)
 data ModuleStmt     = ModuleStmt Id deriving (Show)
 data ModuleBody     = ModuleBody [ModuleBodyVariant] deriving (Show)
-data ModuleBodyVariant  = ModuleBodyParamStmt ParamStmt
-                        | ModuleBodyWire Wire
-                        | ModuleBodyMemory Memory
-                        | ModuleBodyCell Cell
-                        | ModuleBodyProcess Process
+data ModuleBodyVariant  = ModuleBodyParamStmt   ParamStmt
+                        | ModuleBodyWire        Wire
+                        | ModuleBodyMemory      Memory
+                        | ModuleBodyCell        Cell
+                        | ModuleBodyProcess     Process
+                        | ModuleBodyConnStmt    ConnStmt
                         deriving (Show)
 data ParamStmt      = ParamStmt Id (Maybe Constant) deriving (Show)
 data Constant       = ConstantValue   Value
@@ -149,8 +150,7 @@ data Process        = Process ProcStmt [AttrStmt] ProcessBody
 data ProcStmt       = ProcStmt Id deriving (Show)
 data ProcessBody    = ProcessBody 
                         [AssignStmt]
-                        (Maybe Switch)
-                        [AssignStmt] 
+                        [Switch]
                         [Sync] 
                     deriving (Show)
 data AssignStmt     = AssignStmt  DestSigSpec SrcSigSpec
@@ -171,7 +171,7 @@ data Compare        = Compare [SigSpec]
 data CaseBodyVariants   = CaseBodySwitchVariant Switch
                         | CaseBodyAssignVariant AssignStmt
                         deriving (Show)
-data CaseBody       = CaseBody [CaseBodyVariants] deriving (Show)
+data CaseBody       = CaseBody [AssignStmt] [Switch] deriving (Show)
 
 -- Syncs
 data Sync           = Sync SyncStmt [UpdateStmt] deriving (Show)

src/RTLILParser/Parser.hs

@@ -62,6 +62,7 @@ import RTLILParser.Primitives(
    ,pOctal
    ,pEscapedChar
    ,advanceToNextToken
+   ,advanceToFirstToken
     )
 
 -- taken from: https://yosyshq.readthedocs.io/projects/yosys/en/0.47/appendix/rtlil_text.html
@@ -134,7 +135,7 @@ pFile = p <?> name where
     name = "File"
     p =
         File
-        <$> (advanceToNextToken *> pAutoIdxStmt)
+        <$> (advanceToFirstToken *> optionMaybe (try pAutoIdxStmt))
         <*> many pModule
 
 -- Autoindex statements
@@ -189,7 +190,8 @@ pModuleBodyVariant = p <?> name where
         try (ModuleBodyWire         <$> pWire     ) <|>
         try (ModuleBodyMemory       <$> pMemory   ) <|>
         try (ModuleBodyCell         <$> pCell     ) <|>
-        try (ModuleBodyProcess      <$> pProcess  )
+        try (ModuleBodyProcess      <$> pProcess  ) <|>
+        try (ModuleBodyConnStmt     <$> pConnStmt )
 
 pParamStmt :: Parser ParamStmt
 pParamStmt = p <?> name where
@@ -435,11 +437,10 @@ pProcessBody = p <?> name where
         -- with the character 'a', we need to be able to rewind failed
         -- attempts for `pAssignStmt` and `pSwitch` parsers as the first
         -- character being an 'a' would have been consumed.
-        assignStmtsBefore   <- many $ try pAssignStmt
-        switch              <- optionMaybe $ try pSwitch
-        assignStmtsAfter    <- many pAssignStmt
-        syncs               <- many pSync
-        return $ ProcessBody assignStmtsBefore switch assignStmtsAfter syncs
+        assignStmts <- many $ try pAssignStmt
+        switch      <- many $ try pSwitch
+        -- syncs       <- many pSync
+        return $ ProcessBody [] [] []
 
 pAssignStmt :: Parser AssignStmt
 pAssignStmt = p <?> name where
@@ -507,7 +508,12 @@ pCompare = p <?> name where
         <$> pSigSpec `sepBy` (pMaybeWs *> char ',' *> pMaybeWs)
 
 pCaseBody :: Parser CaseBody
-pCaseBody = (CaseBody <$> many pCaseBodyVariant) <?> "CaseBody"
+pCaseBody = p <?> name where
+    name = "CaseBody"
+    p =
+        CaseBody
+        <$> many pAssignStmt
+        <*> many pSwitch
 
 pCaseBodyVariant :: Parser CaseBodyVariants
 pCaseBodyVariant = p <?> name where

src/RTLILParser/Primitives.hs

@@ -6,6 +6,7 @@ module RTLILParser.Primitives(
    ,pOctal
    ,pEscapedChar
    ,advanceToNextToken
+   ,advanceToFirstToken
 ) where
 
 import Control.Monad (void)
@@ -48,11 +49,23 @@ pEol = void (many1 (oneOf "\r\n") <* pMaybeWs)
 -- a comment begins with # and ends at the end of the line
 -- a comment can be be inline, but must still end at the end of the line
 pComment :: Parser String
-pComment = do
-  char '#'
-  comment <- many (noneOf "\r\n")
-  pEol
-  return comment
+pComment = p <?> name where
+    name = "Comment"
+    p =
+        do
+        char '#'
+        comment <- many (noneOf "\r\n")
+        pEol
+        return comment
 
 advanceToNextToken :: Parser ()
-advanceToNextToken = void (pMaybeWs *> many1 (void pComment <|> pEol))
+advanceToNextToken = p <?> name where
+    name = "AdvanceToNextToken" 
+    p = 
+        void (pMaybeWs *> many1 (void pComment <|> pEol))
+
+advanceToFirstToken :: Parser ()
+advanceToFirstToken = p <?> name where
+    name = "AdvanceToFirstToken"
+    p = 
+        void (pMaybeWs *> many (void pComment <|> pEol))