The document discusses the hscParse' function in GHC, which is used to parse Haskell modules. It first gets the dynflags and source file location. It then attempts to parse the module, handling both success and failure. On success, it returns a data structure containing the parsed module and source files. It references functions and tools used in the parsing process like unP, parseModule, mkPState, Alex and Happy.

7. -- compiler/main/HscMain.hs hscParse'関数
hscParse' mod_summary = do
dflags <- getDynFlags
let src_filename = ms_hspp_file mod_summary
maybe_src_buf = ms_hspp_buf mod_summary
liftIO $ showPass dflags "Parser"
{-# SCC "Parser" #-} do
buf <- case maybe_src_buf of
Just b -> return b
Nothing -> liftIO $ hGetStringBuffer src_filename
let loc = mkRealSrcLoc (mkFastString src_filename) 1 1
case unP parseModule (mkPState dflags buf loc) of
PFailed span err ->

8. liftIO $ showPass dflags "Parser"
*** Parser:

9. 詳細:
http://www.kotha.net/ghcguide_ja/7.0.4/
profiling.html#idp19148320

10. liftIO $ dumpIfSet_dyn dflags Opt_D_dump_parsed
"Parser" $ ppr rdr_module
==================== Parser =============
module Queue (
Queue(..)
) where
import Prelude hiding ( head, tail )
class Queue q where {

11. hscParse' :: ModSummary -> Hsc HsParsedModule
hscParse' mod_summary = do
dflags <- getDynFlags
--snip--
case unP parseModule (mkPState dflags buf loc) of
PFailed span err ->
liftIO $ throwOneError (mkPlainErrMsg span err)
POk pst rdr_module -> do
logWarningsReportErrors (getMessages pst)
--snip--
return HsParsedModule {
hpm_module = rdr_module,
hpm_src_files = srcs2
}

12. unP parseModule (mkPState dflags buf loc)
* unP: compiler/parser/Lexer.xで定義
* parseModule: compiler/parser/Parser.y.ppで定義
* mkPState: compiler/parser/Lexer.xで定義

13. http://www.haskell.org/alex/
http://www.haskell.org/happy/

14. -- Parser.y.pp
%monad { P } { >>= } { return }
%lexer { lexer } { L _ ITeof }
%name parseModule module
%name parseStmt maybe_stmt
%name parseIdentifier identifier
%name parseType ctype
%partial parseHeader header
%tokentype { (Located Token) }
http://www.haskell.org/happy/doc/html/sec-monads.html

17. module :: { Located (HsModule RdrName) }
: maybedocheader 'module' modid maybemodwarning
maybeexports 'where' body
{% fileSrcSpan >>= loc ->
return (L loc (HsModule (Just $3) $5 (fst $7)
(snd $7) $4 $1) )}
| body2
{% fileSrcSpan >>= loc ->
return (L loc (HsModule Nothing Nothing
(fst $1) (snd $1) Nothing Nothing
)) }